U.S. Department of the Interior: An Overview 
June 23, 2021 
The U.S. Department of the Interior (DOI) is a federal executive department responsible 
for the administration of lands, minerals, and other resources of the United States. DOI 
Mark K. DeSantis 
describes its mission as protecting and managing the nation’s natural resources and 
Analyst in Natural 
cultural heritage for the benefit of the American people; providing scientific and 
Resources Policy 
scholarly information about those resources and natural hazards; and exercising the 
  
nation’s trust responsibilities and special commitments to American Indians, Alaska 
 
Natives, and island territories under U.S. administration.  
As part of its responsibilities, DOI oversees roughly 420 mil ion acres of federal lands, nearly 55 mil ion  acres of 
tribal lands, more than 700 mil ion  acres of subsurface minerals, and about 2.5 bil ion acres of the outer 
continental shelf. Each year, Congress deliberates legislation that could affect DOI’s management of this vast 
federal estate. Understanding the roles and responsibilities of DOI’s various agencies and offices can be valuable 
when crafting legislation that affects the department’s structure, operations, programs, and funding. 
DOI primarily implements its responsibilities and mission through various bureaus that make up more than 90% 
of the agency’s workforce. These bureaus are the Bureau of Indian Affairs (BIA), Bureau of Indian Education 
(BIE), Bureau of Land Management (BLM), Bureau of Ocean Energy Management (BOEM), Bureau of 
Reclamation (Reclamation), Bureau of Safety and Environmental Enforcement (BSEE), National Park Service 
(NPS), Office of Surface Mining Reclamation and Enforcement (OSMRE), U.S. Fish and Wildlife Service 
(FWS), and U.S. Geological Survey (USGS). Each bureau has a unique mission and set of responsibilities, as wel  
as an organizational structure designed to meet its functional duties. In addition to these bureaus, DOI has 
multiple departmental offices that are responsible for other programs and provide leadership, coordination, and 
services to DOI’s various bureaus and programs. 
The names, structures, and responsibilities of DOI and its various bureaus and offices have evolved since the 
establishment of DOI in 1849. These changes and evolutions are regularly subject to congressional oversight and 
executive branch examination. In recent years, Congress has considered numerous executive branch proposals on 
DOI organization and management, including the transfer of programs between various agencies and offices, the 
creation of new offices and/or bureaus, and the consolidation of DOI boundaries across agencies.  
In December 2020, DOI employed a staff of 60,634 nationwide across its bureaus and offices, according to the 
Office of Personnel Management (OPM). DOI employment figures fluctuate throughout the year, in part because 
some bureaus increase seasonal and part-time staff during the summer months. OPM reports the average total 
DOI employment as 63,175 for the four reporting periods from March 2020 to December 2020. The largest 
bureau within DOI based on number of staff is NPS, which averaged nearly 19,000 employees during 2020—
nearly twice the size of the second-largest bureau, BLM. The smal est bureau by employment is OSMRE, which 
averaged fewer than 400 employees. 
Congress provides discretionary appropriations for DOI through two annual appropriations bil s: the Interior, 
Environment, and Related Agencies bil   and the Energy and Water Development and Related Agencies bil .  From 
FY2017 to FY2021, total DOI appropriations increased 13% in current dollars. Enacted discretionary 
appropriations for FY2021 totaled $15.4 bil ion. 
 
Congressional Research Service 
 
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U.S. Department of the Interior: An Overview 
 
Contents 
Introduction ................................................................................................................... 1 
Establishment of the Department: A Brief History ................................................................ 2 
DOI Today: Leadership, Structure, and Functions ................................................................ 4 
Leadership................................................................................................................ 5 
Recent DOI Reorganization Plans, Proposals, and Issues for Congress............................... 6 
Department-Wide Reorganization Plan .................................................................... 7 
DOI Bureaus: History, Missions, and Current Structures .................................................. 9 
Bureau of Indian Affairs ...................................................................................... 10 
Bureau of Indian Education.................................................................................. 11 
Bureau of Land Management ............................................................................... 12 
Bureau of Ocean Energy Management ................................................................... 14 
Bureau of Reclamation........................................................................................ 15 
Bureau of Safety and Environmental Enforcement................................................... 16 
National Park Service ......................................................................................... 17 
Office of Surface Mining Reclamation and Enforcement .......................................... 18 
U.S. Fish and Wildlife Service.............................................................................. 19 
U.S. Geological Survey ....................................................................................... 21 
Departmental Offices and Programs ........................................................................... 22 
Office of the Secretary ........................................................................................ 22 
Office of the Solicitor ......................................................................................... 23 
Office of the Inspector General............................................................................. 23 
Bureau of Trust Funds Administration (Office of the Special Trustee for American 
Indians).......................................................................................................... 23 
Office of Insular Affairs ...................................................................................... 24 
DOI Employment Levels................................................................................................ 24 
Overview of DOI Appropriations..................................................................................... 27 
DOI Discretionary Appropriations: FY2017-FY2021 .................................................... 27 
DOI Discretionary Appropriations: FY2021, by Agency ................................................ 28 
 
Figures 
Figure 1. Timeline of Selected DOI Agency Establishments and Reorganizations...................... 3 
Figure 2. DOI Organizational Chart of Bureaus and Selected Offices ...................................... 4 
Figure 3. Unified Interior Regional Boundaries.................................................................... 9 
Figure 4. DOI Discretionary Appropriations: FY2017-FY2021 ............................................ 27 
Figure 5. DOI Discretionary Appropriations for FY2021, by Agency .................................... 29 
 
Tables 
Table 1. DOI Employment Trends, by Agency ................................................................... 25 
Table 2. DOI Employment: Inside vs. Outside Washington, DC............................................ 26 
 
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Contacts 
Author Information ....................................................................................................... 29 
  
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U.S. Department of the Interior: An Overview 
 
Introduction 
The Department of the Interior (DOI) is a federal executive department responsible for the 
conservation and use of approximately two-thirds of the estimated 640 mil ion acres of federal 
land. DOI defines its mission as to protect and manage the nation’s natural resources and cultural 
heritage for the benefit of the American people; to provide scientific and scholarly information 
about those resources and natural hazards; and to exercise the country’s trust responsibilities and 
special commitments to American Indians, Alaska Natives, and island  territories under U.S. 
administration.1 Initial y  conceived as a “home department” in 1849 to oversee a broad array of 
internal affairs,2 DOI has evolved to become the nation’s principal land management agency, 
charged with administering roughly 420 mil ion  acres of federal lands, nearly 55 mil ion  acres of 
tribal lands, more than 700 mil ion  acres of subsurface minerals, and about 2.5 bil ion acres of the 
outer continental shelf (OCS).3 
As is the case for many federal departments, Congress examines DOI’s organizational structure 
and functions as part of its lawmaking and oversight functions. Similarly, DOI’s executive branch 
structure and operations are a subject of scrutiny and analysis by various Administrations. Over 
the course of the department’s roughly 170-year history, DOI has evolved in response to the 
needs of the nation and at the behest of Congress and the President. (S
ee Figure 1 for a timeline 
of selected events that influenced the current structure of the department.) Some of these changes 
have been relatively broad in nature, such as the creation of a new agency or regulatory body. 
Other changes have been smal er in scope, such as reorganizations of resources or responsibilities 
among offices or programs.4 
This report is a primer to understanding the organizational framework under which DOI operates, 
and it provides context for how ongoing and potential future reorganizations might affect these 
operations. First, the report provides a timeline of congressional and executive actions that have 
shaped the structure and function of DOI since its establishment. It includes an overview of 
DOI’s history, mission, and current structure, as wel  as recent and ongoing reorganization 
actions. Next, the report provides more detailed information on the mission, leadership, and 
regional office structure of DOI’s bureaus and selected offices.5 The report then details staffing 
levels for the department, including a breakdown of staff located inside and outside the 
Washington, DC, duty station. Final y, it relates the annual discretionary appropriations for the 
department and each of its agencies over the last five years (FY2017-FY2021), with a focus on 
                                              
1  Department  of  the  Interior  (DOI),  
2020/2021  Annual  Performance  Plan  &  2019  Report  (APP&R) ,  p.  3,  at 
https://www.doi.gov/sites/doi.gov/files/uploads/final-appr-03312020_0.pdf (last accessed September 17, 2020). 
2 Robert M. Utley and Barry Mackintosh, 
The Department of Everything Else: Highlights of Interior History  (U.S. 
Department of the Interior, 1989), at https://www.nps.gov/parkhistory/online_books/utley-mackintosh/. Hereinafter 
referred to as Utley and Mackintosh, 
Departm ent of Everything Else. 
3 For data and other information on federal land management, see CRS  Report R42346, 
Federal Land Ownership: 
Overview  and Data, by Carol Hardy Vincent and Laura A. Hanson , and CRS  Report R43429, 
Federal Lands and 
Related Resources: Overview  and Selected Issues for the 117th Congress, coordinated by Katie Hoover. For a brief 
summary of the responsibilities of DOI land  management agencies, see CRS  In Focus IF10585, 
The Federal Land 
Managem ent Agencies, coordinated by Katie Hoover. T he outer continental shelf (OCS) is  defined by statute as all 
submerged  lands  lying seaward  of state coastal waters (3 nautical miles offshore generally) which are under U.S. 
jurisdiction (43 U.S.C.  §1301). 
4 For a more complete discussion  of the history and legal authority pertaining to executive branch reorganization, see 
CRS  Report R44909, 
Executive Branch Reorganization, by Henry B. Hogue. 
5 References in this report to DOI “offices” refer to selected offices only.  
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FY2021. In general, this report contains the most recently available data and estimates as of 
March 2021. A list of CRS experts for DOI bureaus is at the end of the report.  
Establishment of the Department: A Brief History 
Prior to the establishment of DOI in 1849, Congress apportioned domestic affairs in the United 
States across the three original executive departments: Department of State, Department of War 
(now Department of Defense), and Department of the Treasury.6 The Department of State housed 
the nation’s Patent Office, and the Department of War housed the Office of Indian Affairs and the 
Pension Office, which at the time administered pensions solely for military personnel.7 
Meanwhile, the General Land Office (GLO), which oversaw and disposed of the public domain, 
was placed by Congress within the Department of the Treasury because of the revenue generated 
by the GLO from land sales.8 
By the 1840s, the growing federal estate acquired through the Louisiana Purchase, the Mexican-
American War, and the newly negotiated Oregon Territory placed an increasing burden on the 
departments and their leadership.9 In 1848, then-Secretary of the Treasury Robert J. Walker 
submitted to Congress a proposal that would bring together GLO, the Office of Indian Affairs, 
and several other disparate offices and functions under a single, separate executive department.10 
Congress official y established the Department of the Interior on March 3, 1849.11 
In addition to absorbing the functions of the Patent Office, the Office of Indian Affairs, the 
Pension Office, and GLO, the newly established DOI assumed responsibility for a wide range of 
other domestic matters. As part of DOI’s organic legislation, Congress conferred on the Secretary 
of the Interior the “supervisory and appel ate powers” held by the President over the 
commissioner of Public Buildings, as wel  as oversight responsibility for both the U.S. Census 
and the Penitentiary of the District of Columbia.12 Over time, Congress further expanded the 
department’s functions to include the construction of the national capital’s water system, the 
colonization of freed slaves in Haiti,  water pollution control, and the regulation of interstate 
commerce.13 Most of these early activities eventual y were transferred from DOI’s charge as 
Congress began to authorize and create new executive departments and independent agencies to 
handle this growing list of responsibilities. By the 20th century, DOI had evolved to focus 
primarily on protecting and managing natural resources; conducting scientific research; and 
exercising the nation’s trust responsibilities to American Indians, Alaska Natives, and affiliated 
island communities. 
                                              
6 T he Department of State (initially established as the Department of Foreign Affairs) was created in 1781 (1 Stat. 28). 
T he Department of War (1 Stat
.49) and Department of the Treasury (1 Stat. 65) each were established eight years later, 
in 1789. 
7 Utley and Mackintosh, 
Department of Everything Else. 
8 T he General Land Office Act (2 Stat. 716), April 25, 1812, created the General Land Office (GLO) in the Department 
of the T reasury to “ superintend, execute, and perform, all such acts and things, touching or respecting the public  lands 
of the United States,” including  those functions formerly vested in the Secretaries of War and State.  
9 John T . Woolley and Gerhard  Peters, 
The Presidency A to Z, 5th ed. (CQ Press, 2012), p. 315. 
10 
Guide to the Presidency and the Executive Branch, ed. Michael Nelson, 5th ed. (CQ  Press, 2012). 
11 9 Stat. 395. 
12 9 Stat. 395, §§7-10. 
13 DOI, “History of the Interior,” at https://www.doi.gov/whoweare/history (last accessed  December 2020). 
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Figure 1. Timeline of Selected DOI Agency Establishments and Reorganizations 
 
Source:
U.S. Department of the Interior: An Overview 
 
Figure 1. Timeline of Selected DOI Agency Establishments and Reorganizations 
 
Source: Congressional  Research Service  (CRS). See relevant subsections within this report for individual 
citations. 
Notes: *The Fish and Wildlife  Act of 1956 (P.L. 1024) created the U.S. Fish and Wildlife  Service  from the agency 
formerly  known as the Fish and Wildlife  Service. 
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DOI Today: Leadership, Structure, and Functions
U.S. Department of the Interior: An Overview 
 
DOI Today: Leadership, Structure, and Functions 
DOI is a Cabinet-level  department that employs approximately 63,000 full-time employees across 
multiple bureaus and other offices.14 In addition to its headquarters in Washington, DC, DOI has 
staff in roughly 2,400 locations across the United States, including regional offices and field 
locations.15 Each of DOI’s bureaus and offices has a unique mission and set of responsibilities, as 
wel  as a distinct organizational structure that serves to meet its functional duties
. Figure 2 shows 
the DOI organization chart as of March 2021. 
Figure 2. DOI Organizational Chart of Bureaus and Selected Offices 
 
Source: CRS, using information from DOI Office of the Secretary: Department-Wide  Programs,  
Budget 
Justifications  and Performance  Information  Fiscal Year 2021, pp. OS-1, at https://www.doi.gov/sites/doi.gov/files/
fy2021-budget-justification-os-dwp.pdf, and information in the explanatory text of the Consolidated 
Appropriations Act, 2021 (P.L. 116-260), 
Congressional Record,  vol. 166, no. 218, book IV (December  21, 2021), p. 
                                              
14 U.S.  Office of Personnel Management (OPM), FedScope database, Employment cubes, Cabinet -Level Agencies 
parameter set to Department of the Interior, at https://www.fedscope.opm.gov/. T he data reflect “ on-board 
employment” figures based  on the number of employees in pay status at the end of the quarter. Data are published  on a 
quarterly basis  (March, June, September, and December). T otal employment figures in this report reflect the average 
employment totals for the four reported quarters for 2020 (March 2020, June, 2020, September 2020, and December 
2020).  
15 Department of the Interior (DOI), 
Strategic Plan for Fiscal Years  2018-2022, at https://www.doi.gov/sites/
doi.gov/files/uploads/fy2018-2022-strategic-plan.pdf. 
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H8537. Additional information provided via personal communication between CRS and DOI  Office of Legislative 
Affairs,  April 27, 2021. 
Notes: Figure reflects  DOI organizational chart as of this report; however, the organization and reporting status 
of bureaus and offices are subject to change and may be currently under review.  The order of bureaus and 
offices is not intended to reflect a given hierarchy within DOI. CFO = Chief Financial Officer. The Assistant 
Secretary—Policy,  Management and Budget serves  as the DOI’s  CFO. The FY2020 Interior Appropriations law 
approved the Administration’s  proposal to establish the Bureau of Indian Education (BIE) as an independent 
bureau. See explanatory statement accompanying H.R. 1865 (enacted as P.L.  116-94) at House debate, 
Congressional  Record, vol.  165, no. 204, book III (December  17, 2019), p. H11289. Congress now provides funding 
to BIE separately from the Bureau of Indian Affairs (BIA), and DOI considers BIE as an independent bureau from 
BIA. Also,  effective October 1, 2020, many of the trust responsibilities  previously  performed by the Office of the 
Special Trustee for American  Indians were transferred  to a newly established Bureau of Trust Funds 
Administration  (BTFA), according to DOI. This change is reflected with a dashed arrow.  However,  Congress 
indicated that it “does not accept the Department’s  decision to move  forward” with the creation of the BTFA.16 
The special trustee and the principal deputy special trustee continue to report directly to the Secretary.  For 
more  information on the status of this reorganization, see  
“Recent DOI Reorganization Plans, Proposals,  and 
Issues for Congress.” 
Leadership 
The leadership team and senior 
executives of DOI provide oversight 
DOI Presidential Appointees Requiring 
and guidance for the department’s 
Senate Confirmation 
various offices, bureaus, and field 
Secretary  
locations. The department is 
Deputy Secretary  
administered and overseen by the 
Assistant Secretary—Fish,  Wildlife,  and Parks  
Secretary of the Interior (referred to in 
Assistant Secretary—Insular  Affairs  
this report as 
the Secretary) and a 
Assistant Secretary—Land and Minerals Management 
Deputy Secretary, who serves in a 
Assistant Secretary—Policy,  Management, and Budget  
leadership capacity under the 
Assistant Secretary—Water  and Science  
Secretary. The President appoints both 
Assistant Secretary—Indian Affairs  
positions, and the U.S. Senate confirms 
Chairman, National Indian Gaming Commission   
them. (See text box for a full list of 
DOI appointees requiring Senate 
Special Trustee for American  Indians 
confirmation.) Serving under the 
Commissioner,  Bureau of Reclamation  
Secretary and Deputy Secretary are six 
Director,  Bureau of Land Management  
Assistant Secretaries, who oversee 
Director,  U.S. Fish and Wildlife  Service 
DOI’s bureaus and administrative and 
Director,  National Park Service   
programmatic offices. (S
ee Figure 2 
Director,  Office of Surface Mining Reclamation and Enforcement   
for these position titles and 
Director,  U.S. Geological  Survey  
responsibilities.)17 
Inspector General 
In addition to the Secretary, the Deputy 
Solicitor 
Secretary, and the six Assistant 
Source:  U.S. Congress,  Senate Committee  on Homeland 
Security and Governmental  Affairs,  
United States Government 
Secretaries, DOI has other 
Policy and Supporting  Positions (Plum  Book), 116th Cong., 2nd sess., 
congressional y mandated leadership 
committee  print, December  1, 2020 (Washington: GPO, 2020).
 
positions. Similar to other Cabinet-
level agencies, DOI has an inspector general to provide oversight of DOI’s programs, operations, 
                                              
16 Explanatory text of the Consolidated Appropriations Act, 2021 (P.L. 116-260), 
Congressional Record, vol. 166, no. 
218, book IV (December 21, 2021), p. H8537. 
17 43 U.S.C.  §§1452-1476. 
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and management.18 The DOI solicitor heads the Office of the Solicitor, which provides legal 
counsel, advice, and representation for the department.19 The special trustee for American Indians 
is responsible for overseeing the management of financial assets of American Indians held in trust 
by DOI. Final y, the chairperson of the National Indian Gaming Commission oversees an 
independent regulatory body within DOI responsible for administering and promoting economic 
development through gaming on Indian lands.20 Similar to the special trustee, the chairperson of 
the commission operates in an independent capacity separate from the Assistant Secretary—
Indian Affairs (AS-IA). 
Recent DOI Reorganization Plans, Proposals, and 
Issues for Congress 
Congress uses a variety of tools—including authorizing legislation, appropriations legislation, 
and oversight activities—to shape and organize the executive branch and its agencies.21 Often, 
changes are made through internal office transfers and/or budget realignments approved by 
Congress through the appropriations process. In other cases, Congress has considered more 
extensive executive branch reorganization efforts that have broader operational implications for 
an agency or for the department as a whole (see 
“Department-Wide Reorganization Plan”). 
In recent years, Congress has considered, made, or approved several changes to DOI and its 
organizational structure. In addition, some changes to DOI and its agencies have been proposed 
for FY2021 but may not yet be in effect or are stil  under consideration. 
The 115th Congress approved several internal office transfers and realignments, including the 
transfer of appropriations for the Office of Natural Resources Revenue (ONRR) from DOI’s 
Office of the Secretary to Department-Wide Programs.22 In addition, the 116th Congress approved 
the consolidation of ethics staffing and funds from across DOI to the Departmental Ethics Office 
in the Office of the Solicitor, essential y  implementing proposals put forth by DOI in the FY2021 
budget justification and by the Secretary as part of Secretarial Order (S.O.) 3375.23 
In 2016, Congress enacted legislation related to the reorganization of the Office of the Special 
Trustee for American Indians (OST).24 The Indian Trust Asset Reform Act (ITARA) directed the 
Secretary of the Interior to—among other things—“ensure that appraisals and valuations of 
Indian trust property are administered by a single bureau, agency, or other administrative entity 
within the Department” not later than 18 months after enactment.25 Congress subsequently 
approved a transfer of the Office of Appraisal Services within OST to the Office of the 
                                              
18 Inspector General Act of 1978 (P.L. 95-452, 92 Stat. 1101). 
19 60 Stat. 312, 43 U.S.C.  §1455. 
20 Indian Gaming  Regulatory Act, P.L. 100-497, 102 Stat. 2469, 25 U.S.C. §2704. 
21 For a more complete discussion  of Congress’s  constitutional responsibility in establishing the structural organization 
of the executive branch, see CRS  Report R44909, 
Executive Branch Reorganization, by Henry B. Hogue. 
22 DOI, 
Interior Budget in Brief—Fiscal  Year 2018, p. BH-91, at https://edit.doi.gov/sites/doi.gov/files/uploads/
2018_highlights_book.pdf. 
23 DOI, Secretary of the Interior, Order No. 3375, “Improving the Department of the Inter ior’s Ethics Programs 
T hrough Consolidation,” August  14, 2019. For the proposed transfer, see DOI, 
Interior Budget in Brief—Fiscal  Year 
2021, p. DH-32, at https://www.doi.gov/sites/doi.gov/files/uploads/2021-highlights-book.pdf; proposal was  enacted as 
part of P.L. 116-260. 
24 P.L. 114-178. 
25 25 U.S.C.  §5635a. 
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Secretary’s Appraisal and Valuation  Services Office, thereby consolidating al  appraisal activities 
within a single entity.26  
In addition to this transfer, the FY2019 and FY2020 budget justifications for OST proposed to 
transfer OST from the Office of the Secretary to the Office of the AS-IA, wherein OST would 
report to the AS-IA rather than directly to the Secretary (se
e Figure 2).27 In submitting OST’s 
budget request for FY2021, DOI included a proposal to transfer many of the trust responsibilities 
performed by the OST to a newly established Bureau of Trust Funds Administration (BTFA).28 
On August 31, 2020, the then-Secretary of the Interior signed S.O. 3384, which effectuated this 
transfer of duties and established the BTFA (effective October 1, 2020). On the effective date, al  
functions and personnel previously under OST were transferred to BTFA, according to DOI. Per 
S.O. 3384, the BTFA is led by a director, who reports directly to the AS-IA, whereas the positions 
of the special trustee and the principal deputy special trustee continue to report separately to the 
Secretary.29 According to DOI, although the positions of special trustee and principal deputy 
special trustee stil  exist, they are no longer fil ed as of the publication of this report.30 
In the explanatory language for the FY2021 Interior Appropriations Act, Congress stated that it 
“does not accept the Department’s decision to move forward with its budget proposal to create 
[the] BTFA without waiting for the resolution of the proposal through the fiscal year 2021 
appropriations process and over the clear objections of the House of Representatives.”31 Congress 
further expressed that it “expected that the incoming Administration wil  perform its own analysis 
of its trust responsibilities under the 1994 Act and subsequent legislation and that committees of 
jurisdiction, including the House and Senate Appropriations Committees, wil  consider any 
proposals to address the future disposition of OST without prejudice.”32 (For more information, 
see 
“Bureau of Trust Funds Administration (Office of the Special Trustee for American 
Indians).”33 
Department-Wide Reorganization Plan 
The Trump Administration also proposed broader DOI reorganization activities. In March 2017, 
President Trump signed an executive order cal ing on agency leaders to, “if appropriate,” submit a 
                                              
26 T he Administration’s proposal can be found at Office of the Special  T rustee for American Indians (OST ), Budget 
Justifications and Performance Information Fiscal Year 2019 
, OST -1, at https://www.doi.gov/sites/doi.gov/files/
uploads/fy2019_ost_budget_justification.pdf. Congress approved the transfer as part of the FY2019 Interior 
appropriations law (see H.Rept. 116-9).  
27 OST , 
Budget Justifications and Performance Information Fiscal Year 2019 , OST -1-2. 
28 Bureau  of T rust Funds  Administration (BT FA; formerly Office of the Special T rustee for American Indians), 
Budget 
Justifications and Perform ance Inform ation Fiscal Year 20 21, BT FA-5. 
29 DOI, Secretary David Bernhardt, Secretarial Order 3384, 
Creation of the Bureau of Trust  Funds Administration and 
Realignm ent of the Office of the Special Trustee  for Am erican Indians, Land Buy -Back Program  for Tribal Nations, 
and Office of Historical Trust  Accounting , August 31, 2020. 
30 Personal communication between CRS  and DOI Office of Legislative Affairs, April 27, 2021. 
31 Explanatory text of the Consolidated Appropriations Act, 2021 (P.L. 116-260), 
Congressional Record, vol. 166, no. 
218, book IV (December 21, 2021), p. H8537. T he text also states, “ The decision to transfer the functions of OST  
wholesale  into a new bureau  also raises questions  about whether it is  consistent with provisions of the 1994 Indian 
T rust Reform Management Act (P.L. 103-412), which created OST  on a temporary basis until the completion of certain 
trust reforms, or with the existing transition plan for OST  proposed by the Administration and adopted by Congress  in 
fiscal year 2019.” 
32 Ibid. 
33 According to DOI, the Secretary has the legal authority under the Reorganization Plan No. 3 of 1950 to create the 
BT FA. DOI considers the establishment of the BT FA finalized as of October 1, 2020.  
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proposed reorganization plan for their agencies to the director of the Office of Management and 
Budget within 180 days.34 In September 2017, then-Secretary of the Interior Ryan Zinke issued a 
reorganization proposal for DOI in response to this order. Included in this proposal was a plan to 
consolidate the different regional boundaries of each DOI bureau into 12 Unified  Interior 
Regional Boundaries. In August 2018, DOI official y announced the designation of its 12 new 
Unified  Interior Regional Boundaries (s
ee Figure 3).35 According to DOI, the BIA, BIE, and OST 
were excluded from this realignment and retained their existing regional boundaries.36 
In addition to the consolidation of regional boundaries, the plan sought to shift some resources “to 
the field,” potential y  in the form of staff, budget, and/or facilities.37 In FY2019, Congress 
appropriated funds for the reorganization of BLM, FWS, NPS, USGS, and Reclamation.38 The 
Administration’s request indicated that this funding was intended to support the establishment of 
the new Unified Interior Regional Boundaries and to “shift some BLM, FWS, and Reclamation 
headquarters staff to the West.”39 
As part of the broader DOI reorganization effort, the Trump Administration announced plans to 
relocate most BLM positions and personnel based in Washington, DC, to BLM state offices 
across the West and to establish a new BLM headquarters office in Grand Junction, CO. The 
Administration cited potential benefits of the move, including cost savings from lower office 
lease payments and travel costs, as wel  as enhanced integration of policy and operations 
personnel, understanding of western needs, decisionmaking in the field, and partnerships with 
communities and organizations. The relocation was controversial, with some stakeholders raising 
concerns around the costs of relocation, a loss of expertise due to senior staff who did not 
relocate, a possible decline in staff diversity, and potential difficulty for BLM leadership to 
coordinate with DOI management. On August 10, 2020, the Secretary of the Interior signed S.O. 
3382, which formal y established the new Grand Junction headquarters office.40 
                                              
34 Executive Order 13781, “Comprehensive Plan for Reorganizing the Executive Branch,” 82 
Federal Register 13959-
13960, March 13, 2017. 
35 DOI, “ Establishment of Unified Regional  Boundaries  for the Department of the Interior ,” August 29, 2018, at 
https://www.doi.gov/employees/reorg/establishment -unified-regional-boundaries-department -interior (accessed in 
March 2021). 
36 DOI, “Interior Reorganization,” at https://www.doi.gov/employees/reorg (accessed  in March 2021). 
37 Ibid. 
38 Congress appropriated $14.1 million for the reorganization of the Bureau of Land Management ( BLM), U.S.  Fish 
and Wildlife Service  (FWS), National Park Service (NPS), and U.S.  Geological  Survey  (USGS)  through Interior, 
Environment, and Related Agencies Appropriations laws (see H.Rept. 116-9). T he accompanying report does not 
identify the portion of the appropriation for each of the five agencies. T he FY2019 request also sought $3.4 million for 
the reorganization of Reclamation. It appears as though this request was  approved as part of the Energy and Water 
Development Appropriations bill (P.L. 115-244); however, neither the bill language  nor the accompanying report 
specifies funding  for reorganization purposes. 
39 DOI, 
The Interior Budget in Brief Fiscal Year 2019, p. DH-26. 
40 DOI, Secretary of the Interior, Order No. 3382, “Establishment of the Bureau of Land Management’s Headquarters 
in Grand Junction, CO,” August  10, 2020. 
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Figure 3. Unified Interior Regional Boundaries 
 
Source:
U.S. Department of the Interior: An Overview 
 
Figure 3. Unified Interior Regional Boundaries 
 
Source: DOI, “Unified Interior Regional Boundaries,” at https://www.doi.gov/employees/reorg/unified-regional-
boundaries (last accessed April  7, 2021). 
DOI Bureaus: History, Missions, and Current Structures 
Various bureaus comprising more than 90% of the DOI workforce contribute to implement the 
department’s mission and responsibilities.41 The names, structures, and duties of these bureaus 
have evolved over time in accordance with both administrative actions and changes in the 
authorities provided to them by Congress. Below is a brief overview of each bureau, including the 
historical context within which it was created, its organizational structure, and its current mission 
and responsibilities. 
Bureaus appear below in alphabetical order. An “At a Glance” box provides a snapshot of key 
information and data for each bureau. The “Established” date reflects the year in which a bureau 
was created, which in some cases predates the bureau’s assignment to DOI. The “Key Statute” 
listed may represent the initial  legislative  authorization for a bureau to carry out its regulatory 
duties, or it may reference an agency’s organic act, which articulates its mission and/or 
responsibilities. This information does not reflect the full list of governing statutes for DOI 
bureaus, as each bureau is subject to numerous laws. The “Average Staff” listed for each bureau 
reflects the 2020 average of four reporting periods (from March 2020 to December 2020), with 
employment figures rounded to the nearest hundred, as reported to the Office of Personnel 
Management (OPM). DOI employee data are discussed in more detail in the section 
“DOI 
Employment Levels.”  
                                              
41 Calculation based  on OPM Fedscope data.  
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For most agencies, the accompanying map shows an overlay of two different types of boundaries: 
the 12 newly designated unified regional boundaries denoted with numbers 1-12 (as shown in 
Figure 3) and the traditional individual  agency boundaries denoted in different colors.42 
Boundaries for the BIA, BIE, and two agencies that administer offshore energy development 
(BOEM and BSEE) show individual agency boundaries only, because they were not included in 
the newly designated unified regional boundaries, as noted. Although applicable DOI agencies are 
operating with the unified regional boundaries, their individual  boundaries may stil  reflect 
regional office jurisdictions and reporting structures for some agency purposes. 
Bureau of Indian Affairs 
At a Glance: Bureau of Indian Affairs (BIA) 
Established:      1824 
Key Statute:     Snyder Act of 1921 (42 Stat. 208)
 
Mission:            “To enhance the quality of life,  to promote 
economic  opportunity, and to carry out the responsibility  to 
protect and improve the trust assets of American  Indians, 
Indian Tribes,  and Alaska  Natives.”* 
Leadership:       Director 
Headquarters:  Washington, DC 
Average Staff:   7,100 (including staff from  the Bureau of 
Indian Education)** 
Regions:   
                          Unified Regions: N/A                           
 
                          Agency Regions: 12 (colored)             
Source:  *Bureau of Indian Affairs,  “About Us,” at https://www.bia.gov/about-us. 
Notes: **OPM Fedscope data. This figure includes employees  of both BIA and BIE , as Fedscope does not distinguish 
between the two bureaus. The FY2021 budget justifications for BIA and BIE estimated  roughly 4,000 and 2,500 ful -
time-equivalent staff, respectively,  for FY2020, as distinct from the on-board employment as reported in Fedscope.
 
Established in 1824, the Bureau of Indian Affairs (BIA) is the oldest bureau within DOI, 
predating the department by 25 years. Then-Secretary of War John C. Calhoun established the 
Office of Indian Affairs within the War Department to help centralize what was at the time a 
fractured administrative approach to Indian policy and relations in the United States.43 It was not 
until 1832 that Congress official y recognized the Office of Indian Affairs as a bureau of the War 
Department by establishing a commissioner to oversee the agency.44 The Office of Indian Affairs 
was transferred to DOI in 1849, when the department was created. DOI formal y adopted the 
name 
Bureau of Indian Affairs in 1947.45 
                                              
42 Unless otherwise noted, the individual agency boundaries  are shown as they existed prior to the August 2018 
establishment of the unified regional boundaries. 
43 William S.  Belko, “John C. Calhoun and the Creation of the Bureau of Indian Affairs: An Essay o n Political Rivalry, 
Ideology, and Policymaking in the Early Republic,”  
The South Carolina Historical  Magazine 105, no. 3 (2004), p. 194, 
at http://www.jstor.org/stable/27570693. 
44 From an act dated  July 9, 1832, ch. 174, §1, 4 Stat. 564. 
45 T he Office of Indian Affairs was  redesignated  the Bureau  of Indian Affairs (BIA) by Secretarial Order No. 2362. 
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BIA provides services to federal y recognized American Indian and Alaska Native tribes and their 
nearly 2 mil ion  members.46 These services include disaster relief and road construction, as wel  
as the operation and funding of law enforcement, tribal courts, and detention facilities, among 
others. The bureau is also responsible for protecting and administering assets on tribal lands, 
including the management of 55 mil ion  surface acres and 59 mil ion acres of subsurface mineral 
estates held in trust by the United States.47 
The BIA is administered by a director who oversees the agency’s functions and reports to the 
Assistant Secretary—Indian Affairs. Similar to other DOI agencies, the BIA has a three-tiered 
organizational structure, with leadership and senior executives operating from headquarters in 
Washington, DC, and 12 regional offices that oversee 85 field offices (referred to as 
agencies by 
the BIA); these agencies deliver program services directly to tribal communities.48 
Bureau of Indian Education49 
At a Glance: Bureau of Indian Education (BIE) 
Established:      2006 
Key Statute:     Snyder Act of 1921 (42 Stat. 208)
 
Mission:            “To provide quality education opportunities 
from early childhood through life in accordance with a tribe’s 
needs for cultural and economic wel -being,  in keeping with the 
wide diversity of Indian tribes and Alaska  Native vil ages  as 
distinct cultural and governmental entities.”* 
Leadership:        Director 
Headquarters:   Washington, DC 
Average Staff:    7,100 (including staff from  the Bureau of 
Indian Affairs)** 
Regions:   
 
                          Unified Regions: N/A                           
                          Agency Regions: 12 (colored)             
Source:  *Bureau of Indian Education, “About Us,” at https://www.bia.gov/about-us. 
Notes: **OPM Fedscope data. This figure includes employees  of both BIA and BIE , as Fedscope does not distinguish 
between the two bureaus. The FY2021 budget justifications for BIA and BIE estimated  roughly 4,000 and 2,500 ful -
time-equivalent staff (not on-board employment),  respectively,  for FY2020.
 
BIA  previously was responsible for managing the bureau’s elementary, secondary, and 
postsecondary schools and for supporting additional Indian education activities through BIA’s 
Office of Indian Education Programs. In 2006, the Secretary of the Interior separated the BIA 
education programs from the rest of BIA and placed them in a new Bureau of Indian Education 
(BIE).50 However, both BIA and BIE were funded as part of DOI’s broader Indian Affairs budget 
until FY2020, when the two bureaus were funded separately. 
                                              
46 Figures  provided to CRS  by DOI, Office of Congressional and Legislative Affairs, June 2021.  
47 BIA, “What We Do,” at https://www.bia.gov/bia/ots/what-we-do.   
48 DOI, Bureau  of Indian Affairs, 
Budget Justifications and Performance Information Fiscal Year 2021 , p. IA-RES-5, 
at https://www.bia.gov/sites/bia.gov/files/assets/as-ia/obpm/BIA_FY2021_Greenbook-508.pdf. 
49 For a more complete discussion  of BIE and its various duties,  see CRS  Report RL34205, 
Indian Elementary-
Secondary Education: Program s, Background, and Issues, by Cassandria  Dortch. 
50 DOI, Indian Affairs, 
Budget Justifications Fiscal Year 2008, pp. IA-EDUC-5 to -6. 
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For FY2020, the Trump Administration proposed funding BIE independently from BIA and 
submitted a separate budget justification for each bureau.51 In proposing a separate budget 
structure for BIE, the Administration sought to “strengthen BIE as an independent bureau with a 
separate budget structure to advance ongoing BIE reforms to Cimprove learning and student 
outcomes” and to reduce overlapping functions between BIA and BIE to “better deliver services 
to schools, maximize efficiency, and build capacity within BIE.”52 In the explanatory language for 
the FY2020 Interior Appropriations law, Congress approved the establishment of BIE as an 
independent bureau with a separate budget structure from BIA.53 
The BIE education system serves approximately 46,000 students through 169 
elementary/secondary schools and 14 dormitories located in 23 states, as wel  as 1,500 students 
through 2 postsecondary institutions in 2 states.54 BIE-funded elementary and secondary schools 
may be operated directly by the bureau, by tribes and tribal organizations, or through a 
cooperative agreement with a public school district. BIE also supports public school students, 29 
tribal y controlled colleges and universities, and two tribal technical colleges. BIE is administered 
by a director, who oversees the bureau’s functions and reports to the Assistant Secretary of Indian 
Affairs. 
Bureau of Land Management 
At a Glance: Bureau of Land Management (BLM) 
Established:         1946 
Key Statute:        Federal  Land Policy and Management Act of 
1976 (90 Stat. 2744)
 
Mission:              “To sustain the health, diversity and 
productivity of public lands for the use and enjoyment of present 
and future generations.”* 
Leadership:        Director 
Headquarters:   Grand Junction, CO 
Average Staff:   9,700 
Regions:   
                          Unified Regions: 12 (numbered)                           
 
                          Agency Regions: 12 (colored)            
 
Source:
  *BLM, “Our Mission,” at https://www.blm.gov/about/our-mission. 
The Bureau of Land Management (BLM) was created in 1946, following the merger of DOI’s 
General Land Office (GLO) and the U.S. Grazing Service, known previously as the Division of 
Grazing Control and subsequently as the Division of Grazing.55 BLM manages 244 mil ion  acres                                               
51 T he budget  justifications for the Bureau of Indian Affairs and the Bureau  of Indian Education are located on the DOI 
website  at https://www.doi.gov/budget/appropriations/2020. 
52 DOI, 
Fiscal Year 2020: The Interior Budget in Brief, p. BH-95. 
53 U.S.  Congress, House  Committee on Appropriations, 
Further Consolidated Appropriations Act, 2020, committee 
print, 116th Cong., 2nd sess., January 2020 (Washington: GPO, 2020), p. 604. 
54 DOI, Bureau  of Indian Education, 
Budget Justifications and Performance Information Fiscal Year 2021 , p. BIE-ES-
1 and BIE-OIEP-6, at https://www.doi.gov/sites/doi.gov/files/uploads/fy2021-budget -justification-bie.pdf. T he three-
year average daily student estimate (referred to as “Average Daily Membership”) is roughly 41,000.  
55 DOI, Secretary Harold L. Ickes, Secretarial Order 2225, July 15, 1946. Implemented as part of Reorganization Plan 
No. 3 of 1946 (11 
Federal Register 7875, 60 Stat. 1097), effective July 16, 1946. T he GLO, created by Congress  in 
1812, helped convey lands to pioneers settling western lands  in the early 19 th century. T he U.S. Grazing  Service  (then 
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of public land
—roughly 10% of the total U.S. land area. The vast majority of this land (more than 
99%) is located in 12 western states, including Alaska.56 The agency also is responsible for more 
than 700 mil ion  acres of the federal onshore subsurface mineral estate and provides technical 
supervision of mineral development on about 59 mil ion  acres of BIA mineral estate.57 BLM 
manages public lands under the dual framework of multiple use and sustained yield, as required 
under the Federal Land Policy and Management Act of 1976.58 These uses include a wide range 
of activities, such as energy and mineral development, livestock grazing, and recreation. 
In 2020, BLM  relocated its primary headquarters from Washington, DC, to a new office in Grand 
Junction, CO (see 
“Department-Wide Reorganization Plan” for more information). The new BLM 
headquarters is home to the agency’s leadership, which provides strategic direction and oversight 
of BLM’s national-level  activities. BLM has indicated that about 60 positions from programs 
with “inherently DC-based responsibilities, like legislative, regulatory and public affairs, budget, 
and Freedom of Information Act compliance, as well as the Deputy Director for Policy and 
Programs” wil  remain in the Washington, DC, area.59 In addition to the Grand Junction, CO, and 
Washington, DC, offices, 12 state offices—which are akin to the regional office structure of other 
agencies—carry out BLM’s mission within their respective geographical areas of jurisdiction.60 
Reporting to these 12 state offices are numerous district offices, which are further divided into 
localized  field offices. Field offices oversee the day-to-day management of public land resources 
and the on-the-ground delivery of BLM programs and services. BLM also has several national-
level support and service centers.  
                                              
known as  the Division of Grazing  Control) was established  in 1934 to administer grazing on public  rangelands.  (T aylor 
Grazing  Act, 48 Stat. 1269.) 
56 BLM, 
Public Land Statistics 2019 (as of June 2020), T able 1-4, at https://www.blm.gov/sites/blm.gov/files/
PublicLandStatistics2019.pdf. Hereinafter referred to as “ BLM, 
Public Land Statistics 2019.”
 
57 BLM, 
Public Land Statistics 2019. 58 Federal Land Policy and Management Act of 1976 (FLPMA), 43 U.S.C. §§1701, et seq.  FLPMA defines 
multiple 
use as “  ... the management of the public lands and their various resource values  so that they are utilized in the 
combination that will best meet the present and future needs  of the American people ... ” and 
sustained yield as  “  ... the 
achievement and maintenance in perpetuity of a high -level annual or regular periodic output of the various renewable 
resources of the public  lands  consistent with mult iple use” (43 U.S.C.  §1702(h)). Although BLM was  established in 
1946, FLPMA is considered the agency’s 
organic act, as it consolidated and articulated the agency’s responsibilities. 
59 BLM, “Headquarters Move West,” at https://www.blm.gov/office/national-office/hq-move-west (accessed on May 
11, 2021). 
60 43 C.F.R. §1821.10a. 
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Bureau of Ocean Energy Management 
At a Glance: Bureau of Ocean Energy Management (BOEM) 
Established
U.S. Department of the Interior: An Overview 
 
Bureau of Ocean Energy Management 
At a Glance: Bureau of Ocean Energy Management (BOEM) 
Established:        2011 
Key Statute:       Outer Continental Shelf Lands Act of 1953 (67 
Stat. 462) 
Mission:             “To manage development of U.S. outer 
continental shelf energy and mineral  resources  in an 
environmental y  and economical y  responsible  way.”* 
Leadership:        Director 
Headquarters:   Washington, DC 
Average Staff:    600 
Regions:   
                          Unified Regions: N/A                           
 
                          Agency Regions: 4 (colored)                    
Source:  *BOEM, “About BOEM,” at https://www.boem.gov/About-BOEM/. 
Established in 2011, the Bureau of Ocean Energy Management (BOEM) manages development of 
the nation’s energy and mineral resources on nearly 2.5 bil ion acres of the U.S. outer continental 
shelf (OCS).61 The Outer Continental Shelf Lands Act (OCSLA) of 1953 defines the OCS as al  
submerged lands lying seaward of state coastal waters that are subject to federal jurisdiction.62 
Under OCSLA, the Secretary of the Interior has the authority to manage the development of the 
OCS.63 
Prior to BOEM’s establishment, the Secretary delegated the leasing and management authority 
granted by OCSLA to the DOI agency known as the Minerals Management Service (MMS).64 
During its existence, MMS had three primary responsibilities concerning offshore development: 
resource management, safety and environmental oversight and enforcement, and revenue 
collection. Following the 
Deepwater Horizon oil spil  in 2010, concerns about perceived conflicts 
between these three missions prompted then-Secretary of the Interior Ken Salazar to reorganize 
the agency. MMS was formal y dissolved, and three new units were established within DOI: 
BOEM, the Bureau of Safety and Environmental Enforcement (BSEE), and the Office of Natural 
Resource Revenue (ONRR). 
The agency’s leadership—led by a director—is headquartered in Washington, DC, and divides 
itself among three programmatic offices covering strategic resource programs, offshore renewable 
energy programs, and environmental analysis and science. Meanwhile, regional offices oversee 
                                              
61 Although the order dividing  the Minerals Management Service (MMS)  into three separate entities was issued  in 
2010, the Bureau of Ocean Energy Management (BOEM) was  not formally established until October 1, 2011. Prior to 
that, an interim agency known as t he Bureau of Ocean Energy Management, Regulation and Enforcement  was in place. 
For more information, see BOEM, “T he Reorganization of the Former MMS,” at https://www.boem.gov/about-boem/
reorganization/reorganization-former-mms. 
62 Outer Continental Shelf Lands Act of 1953, 42 U.S.C. §§1331-1356b. T he definition of the outer continental shelf 
(OCS)  is  at 43 U.S.C.  §1331(a). 
63 For a discussion  of state and federal waters, see  CRS  Report RL33404, 
Offshore Oil and Gas Development: Legal 
Fram ework, by Adam Vann. 
64 Secretarial Order 3071, January 19, 1982, established the MMS  following  a number  of hearings and investigations 
into allegations of fraud, lack of oversight, and inadequate collection of royalties from oil and gas production on federal 
lands  and the OCS. 
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on-the-ground operations and policy implementation in the four OCS regions in the Atlantic, the 
Gulf of Mexico, the Pacific, and Alaska.65 
Bureau of Reclamation 
At a Glance: Bureau of Reclamation (Reclamation) 
Established:        1902 
Key Statute:       Reclamation Act of 1902 (32 Stat. 338) 
Mission:             “To manage, develop,  and protect water and 
related resources  in an environmental y  and economical y 
sound manner in the interest  of the American  public.”* 
Leadership:        Commissioner 
Headquarters:   Washington, DC 
Denver,  CO (administrative) 
Average Staff:    5,300 
Regions:   
 
                          Unified Regions: 12 (numbered)                           
                          Agency Regions: 6 (colored)            
 
Source:  *Bureau of Reclamation, “About Us—Mission/Vision,”  at https://www.usbr.gov/main/about/mission.html. 
Notes: This map reflects  the agency regional boundaries for the Bureau of Reclamation as of March 2021. Prior to 
2018, Reclamation had five agency regions; however, the agency added a sixth region and revised regional 
boundaries to align with the new unified regional boundary structure. 
In 1902, Congress passed the Reclamation Act, which set aside federal dollars to fund irrigation 
projects and large-scale dam construction in the arid and rapidly expanding western United 
States.66 Shortly thereafter, Congress established the U.S. Reclamation Service as a program 
within the U.S. Geological Survey (USGS). In its first five years, the service began work on more 
than 30 projects across the American West. In 1907, the Secretary of the Interior elevated the 
program to an independent bureau within DOI before renaming it the Bureau of Reclamation 
(Reclamation) in 1923.67 Since its establishment, Reclamation has constructed or overseen the 
construction of more than 600 dams and reservoirs across the western United States.68 
Beneficiaries of reclamation projects general y repay the costs for construction and operations of 
                                              
65 BOEM, 
Budget Justifications and Performance Information Fiscal Year 2021, p. 83, at https://www.boem.gov/sites/
default/files/documents/about-boem/budget/FY%202021%20Budget%20Justification.pdf. T he Gulf  of Mexico, 
California, and Alaska regions are managed from offices in New  Orleans, LA; Camarillo, CA;  and Anchorage, AK, 
respectively. BOEM’s Office of Renewable  Energy Programs based  in Sterling, VA,  oversees wind  and water 
development in t he Atlantic OCS region. T he Gulf  of Mexico Regional  Office oversees oil and  gas activities in the 
Atlantic OCS;  however, no active OCS  oil and gas  leases  exist in  the region, nor are there any proposed lease sales 
under the proposed Five-Year Leasing  Program 2017-2022. 
66 Newlands  Reclamation Act, P.L. 57-161, 32 Stat. 388 (enacted June 17, 1902). Initially, the Reclamation Act set 
aside  funding  for projects across 13 western states. Over time, Reclamation expanded the number of states within 
which it worked.  Reclamation now manages projects constructed by the agency in 17 states (referred to as 
Reclam ation 
states): AZ, CO, CA, ID, KS,  MT , NE, ND, NM, NV,  OK, OR,  SD,  T X, UT , WA, WY.  
67 Mary C. Rabbitt, 
A Brief History of the United States Geological Survey, U.S.  Department of the Interior, 1975, pp. 
3-4, at https://pubs.er.usgs.gov/publication/70039204. Hereinafter referred to as Rabbitt, 
United States Geological 
Survey. 
68 Reclamation, “About Us,” at https://www.usbr.gov/main/about/. 
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these facilities to the federal government over extended terms (in some cases without interest). 
The exception are costs deemed “federal” in nature, as federal costs are nonreimbursable.69 
Although Reclamation original y  focused almost entirely on building new water storage and 
diversion projects, the agency now largely focuses on the operation and maintenance of existing 
facilities.70 Reclamation’s mission also has expanded to include support for other efforts to 
improve water supplies in the western United States, such as promoting water reuse and recycling 
efforts, desalination projects, and Indian water rights settlements. 
A presidential y  appointed commissioner oversees the work of Reclamation and, along with other 
senior-level executives, manages the overal  operations of the agency from its headquarters in 
Washington, DC. Due to the number of projects and employees based in western states, 
Reclamation also maintains federal offices in Denver, CO, which administer many of 
Reclamation’s programs, initiatives, and activities. These programs include efforts that address 
dam safety, flood hydrology, fisheries and wildlife resources, and research programs that seek to 
improve management and increase water supplies. In addition, six regional offices manage 
Reclamation’s water projects and oversee various local area offices responsible for the day-to-day 
operations of the nearly 180 projects currently under the agency’s authority.71 
Bureau of Safety and Environmental Enforcement 
At a Glance: Bureau of Safety and Environmental Enforcement (BSEE) 
Established:        2011 
Key Statute:       Outer Continental Shelf Lands Act of 1953 
(67 Stat. 462) 
Mission:             “To promote safety, protect the 
environment,  and conserve resources  offshore through 
vigorous regulatory oversight and enforcement.”* 
Leadership:        Director 
Headquarters:   Washington, DC 
Average Staff:    800 
Regions:   
                          Unified Regions: N/A                           
 
                          Agency Regions: 4 (colored)             
Source:  *BSEE, “About Us,” at https://www.bsee.gov/about-bsee. 
Following the 2011 restructuring of MMS (see 
“Bureau of Ocean Energy Management”), the 
Bureau of Safety and Environmental Enforcement (BSEE) inherited the safety and environmental 
enforcement functions previously carried out by MMS.72 These functions are primarily concerned 
with the offshore energy industry on the OCS—largely oil and natural gas production. BSEE’s 
                                              
69 Nonreimbursable costs include costs allocated to fish and wildlife enhancement and recreation, among other things. 
For more information on Reclamation project rep ayment, see CRS  In Focus IF10806, 
Bureau of Reclam ation Project 
Authorization and Financing, by Charles V.  Stern. 
70 For a more comprehensive discussion  of Reclamation’s functions and responsibilities, see CRS  Report R46303, 
Bureau of Reclam ation: History, Authorities, and Issues for Congress, by Charles V.  Stern and Anna E. Normand. 
71 T he regional offices are the Columbia-Pacific Northwest Region, Missouri  Basin  Region, Upper Colorado Basin 
Region, Lower Colorado Basin Region,  California-Great Basin Region, and Arkansas-Rio Grande-T exas Gulf  Region. 
72 See  footnot
e 61. 
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responsibilities include regulation of worker safety, emergency preparedness, environmental 
compliance, and resource conservation.73 
BSEE is administered by a director based out of the agency’s headquarters in Washington, DC. 
The agency also has a second headquarters location in Sterling, VA, that oversees many of 
BSEE’s national programs and provides technical and administrative support for the bureau.74 To 
carry out the duties of the department, BSEE coordinates between leadership in these two 
locations and staff operating across three regional offices (serving Alaska, the Pacific, and the 
Gulf of Mexico OCS regions),75 and five Gulf Coast district offices (Houma, Lafayette, Lake 
Charles, and New Orleans, LA, and Lake Jackson, TX).76 Senior leadership sets the policies and 
performance goals implemented at these local offices across the agency’s six national programs.77 
National Park Service 
At a Glance: National Park Service (NPS) 
Established:       1916 
Key Statute:      National Park Service  Organic Act of 1916 
(39 Stat. 535) 
Mission:            “To preserve  unimpaired the natural and 
cultural resources  and values of the National Park System for 
the enjoyment,  education, and inspiration of this and future 
generations.”*  
Leadership:        Director 
Headquarters:   Washington, DC 
Average Staff:    18,900 
Regions:   
                          Unified Regions: 12 (numbered)                           
 
                          Agency Regions: 7 (colored)
 
Source:  *NPS, “About Us,” at https://www.nps.gov/aboutus/index.htm. 
In 1916, the National Park Service Organic Act (Organic Act) centralized administration of the 
nation’s national parks and national monuments. With the Organic Act, Congress created the 
National Park Service (NPS) and established the agency’s dual mandate—to protect the country’s 
natural and cultural resources while providing for their public use and enjoyment.78 In 
undertaking that mission, NPS administers approximately 80 mil ion  acres of federal land, 
including 423 units that comprise the National Park System across al  50 states and U.S. 
territories. 
                                              
73 Bureau  of Safety and Environmental Enforcement (BSEE), “What We Do,” at https://www.bsee.gov/what-we-do. 
74 BSEE,  “Our Organization,” at https://www.bsee.gov/about-bsee/our-organization.  
75 T he Gulf  of Mexico Regional Office oversees activities for the Atlantic OCS region.  
76 BSEE  shares regional offices in New  Orleans, LA, Camarillo, CA, and Anchorage, AK, with BOEM staff . 
77 BSEE,  “National Programs,” at https://www.bsee.gov/about-bsee/our-organization/national-programs. T hese 
programs are Oil Spill  Preparedness Program, Environmental Compliance Program, National Investigations Program, 
Office of Offshore Regulatory Programs, National Enforcement Program, and Office of Administration. 
78 39 Stat. 535.  
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A park superintendent oversees each NPS unit and manages day-to-day administration in 
accordance with both the agency’s mission and any laws and regulations specific to the unit.79 
These units and their leadership report to seven regional directors, who oversee park management 
and program implementation across geographic regions. At the national level, NPS is led by a 
director and senior executives who manage national programs, policy, and budget from the 
agency’s headquarters in Washington, DC.80 
Office of Surface Mining Reclamation and Enforcement 
At a Glance: Office of Surface Mining Reclamation and Enforcement (OSMRE) 
Established:        1977 
Key Statute:       Surface Mining Control and Reclamation Act 
of 1977 (91 Stat. 445) 
Mission:              “To ensure that coal mines are operated in a 
manner that protects citizens and the environment during 
mining and assures that the land is restored  to beneficial use 
fol owing mining,  and to mitigate the effects of past mining by 
aggressively  pursuing reclamation  of abandoned coal mines.”*  
Leadership:        Director 
Headquarters:   Washington, DC 
Average Staff:    400 
Regions:   
 
                          Unified Regions: 12 (numbered)                           
                          Agency Regions: 3 (colored)             
Source:  *OSMRE, “Our Mission and Vision,”  at https://www.osmre.gov/about/MissionVision.shtm. 
Notes: OSMRE Western Region works with three tribal partners to carry out the Surface Mining Control and 
Reclamation Act (SMCRA): the Crow Tribe, the Hopi Tribe, and the Navajo Nation. These partners are 
represented  by the dark blue sections of the Regional Map above but do not together comprise  a separate region. 
States colored  in grey are non-primacy states with no ongoing coal mining operations.
 
The Office of Surface Mining Reclamation and Enforcement (OSMRE) was established as a 
bureau within DOI following passage of the Surface Mining Control and Reclamation Act 
(SMCRA) in 1977.81 The law authorized the new agency to carry out and administer a nationwide 
program to regulate coal mining in the United States. Under SMCRA, OSMRE provides grants to 
states and tribal communities to reclaim abandoned coal mines.82 It also regulates active surface 
coal mining operations to minimize adverse impacts to the environment and local communities.83 
                                              
79 NPS park superintendents sometimes are responsible for managing mult iple units based  on size, capacity, and 
geographic proximity. 
80 NPS, “Organizational Structure of the National Park Service,” at https://www.nps.gov/aboutus/organizational-
structure.htm. 
81 Surface  Mining Control and Reclamation Act (SMCRA),  P.L. 95-87, 91 Stat. 507, 30 U.S.C. §§1201-1328 (enacted 
August,  3, 1977).  
82 For more information, see CRS  Report R46266, 
The Abandoned Mine Reclamation Fund: Reauthorization Issues in 
the 116th Congress, by Lance N. Larson. 
83 For more information, see CRS  Report R46610, 
Reclamation of Coal Mining Operations: Select Issues and 
Legislation, by Lance N. Larson. 
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U.S. Department of the Interior: An Overview 
 
In addition, SMCRA authorizes OSMRE to issue federal payments to the United Mine Workers of 
America coal mineworker health and pension benefits plans.84 
OSMRE serves as the lead regulatory authority over surface coal mining and reclamation 
activities for states and tribal communities under the authority granted by Title V of SMCRA.85 
SMCRA  does, however, al ow OSMRE to delegate regulatory primacy to states and tribes upon 
demonstration that a given state or tribe has established regulatory requirements consistent with 
federal standards.86 OSMRE operates in an oversight capacity for primacy states. To date, no tribe 
has attained this delegated authority.87 
OSMRE fulfil s its missions through a three-tiered organizational structure: headquarters in 
Washington, DC; three regional offices (Appalachian, Mid-continent, and Western); and multiple 
area and field offices that report directly to the regional offices.88 
U.S. Fish and Wildlife Service 
At a Glance: U.S. Fish and Wildlife Service (FWS) 
Established:        1940 
Key Statute:       Fish and Wildlife  Act of 1956 (70 Stat. 1120)  
Mission:             “To conserve,  protect and enhance fish, 
wildlife  and plants and their habitats for the continuing benefit 
of the American  people.”* 
Leadership:        Director 
Headquarters:   Washington, DC 
Fal s Church, VA 
Average Staff:    8,300 
Regions:   
                          Unified Regions: 12 (numbered)                           
 
                          Agency Regions: 8 (colored) 
Source:  *FWS, “About the U.S. Fish and Wildlife  Service,”  at https://www.fws.gov/help/about_us.html.
 
The U.S. Fish and Wildlife  Service (FWS) is the principal federal agency tasked with the 
conservation, protection, and restoration of fish, wildlife, and natural habitats across the United 
States and its insular territories. The history of FWS can be traced back to the creation of two 
now-defunct agencies in the late 1800s: the U.S. Commission on Fish and Fisheries in the 
Department of Commerce and the Division of Economic Ornithology and Mammalogy in the 
Department of Agriculture.89 The successors to these two agencies were subsequently transferred 
to DOI in 1939 and subsequently consolidated, creating a single agency known at the time as the 
                                              
84 30 U.S.C.  §1232. For more information, see CRS  In Focus  IF11370, 
Health and Pension Benefits for United Mine 
Workers  of Am erica Retirees:  Recent Legislation, by John J. T opoleski.  
85 30 U.S.C.  §1254. 
86 30 U.S.C.  §1253. 
87 OSMRE,  “Non-Primacy States and T ribes,” at https://www.osmre.gov/programs/AMLIS/nonPrimacyST .shtm. 
88 OSMRE,  “Who We Are,” at https://www.osmre.gov/about.shtm. 
89 For a more complete discussion  of the history of FWS, see  CRS  Report R45265, 
U.S. Fish and Wildlife  Service: An 
Overview,  by R. Eliot Crafton. 
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Fish and Wildlife  Service.90 In 1956, Congress passed the Fish and Wildlife Act of 1956, which 
established the U.S. Fish and Wildlife  Service.91 
The FWS has a primary-use mission “to conserve, protect and enhance fish, wildlife and plants 
and their habitats for the continuing benefit of the American people.”92 Among its responsibilities, 
FWS manages the National Wildlife  Refuge System (NWRS) pursuant to the National Wildlife 
Refuge System Administration Act of 1966 as wel  as other statutes.93 The NWRS is a network of 
lands and waters set aside to conserve the nation’s fish, wildlife, and plants that has grown to 
include more than 560 refuges, 38 wetland management districts, and other protected areas. More 
than 836 mil ion  acres of lands and waters comprise the NWRS; of these lands and waters, 146 
mil ion  acres are classified as National Wildlife  Refuges.94 
In addition, FWS, along with the National Oceanic and Atmospheric Administration (NOAA) in 
the Department of Commerce, is responsible for implementing the Endangered Species Act 
(ESA).95 The purpose of the ESA is to protect species that are in danger of becoming extinct or 
could be in danger of becoming extinct in the near future.96 FWS also assists in international 
conservation efforts, enforces federal wildlife laws, and administers grant funds to states and 
territories for fish and wildlife programs. 
Similar to most DOI agencies, FWS has a three-tiered organizational structure composed of 
national, regional, and local field offices across the United States. The headquarters office—led 
by an agency director—is split between two locations in Washington, DC, and Fal s Church, VA, 
which together have primary responsibility for policy formulation and budgeting across the 
agency’s program areas.97 Eight regional offices oversee FWS field offices and science centers 
across the United States and U.S. territories, which implement these policies and programs at the 
local level.98  
                                              
90 Reorganization Plan Number III of 1940, 5 U.S.C  Appendix —Reorganization Plans. 
91 Fish and Wildlife Act of 1956, 70 Stat. 1119, 16 U.S.C. §742a. 
92 FWS,  “About the U.S. Fish and Wildlife Service,”  at https://www.fws.gov/help/about_us.html. 
93 National Wildlife Refuge  System Administration Act of 1966, P.L. 89-669, 16 U.S.C. §§668dd  et seq. (Note: 
Congress  later passed the National Wildlife Refuge  System Im provement Act in 1997 [P.L. 105-57, 111 Stat. 1252], 
which amended  the 1966 law by establishing the refuge system’s mission and providing what is considered  to be the 
organic legislation for its management  by FWS). While the Administration Act provided for consolidation of the 
system, other statues also provide authority for certain system activities.  
94 T he 836 million acres that comprise the National Wildlife Refuge System also include  waterfowl  production areas, 
coordination areas, and more than 685 million acres of national m onument areas that are located outside National 
Wildlife Refuge  boundaries.  T hese national monument areas are National Wildlife Refuge  System lands and 
submerged  lands  and waters within portions of four marine national monuments that are managed or co -managed by 
FWS  pursuant to presidential proclamations. T hese national monuments were established under  the authority granted 
by the Antiquities Act (54 U.S.C.  §320301). 
95 Act of December 28, 1973, P.L. 93-205, 87 Stat. 884. 16 U.S.C. §§1531-1544. 
96 16 U.S.C.  §1531(b). For a more complete discussion  of the ESA, see  CRS  Report R46677, 
The Endangered Species 
Act: Overview and Im plem entation, by Pervaze A. Sheikh, Erin H. Ward, and R. Eliot Crafton .  
97 FWS,  “About the U.S. Fish and Wildlife Services,”  at https://www.fws.gov/help/about_us.html. 
98 FWS,  “Offices,” at https://www.fws.gov/offices. 
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U.S. Geological Survey 
At a Glance: U.S. Geological Survey (USGS) 
Established
U.S. Department of the Interior: An Overview 
 
U.S. Geological Survey 
At a Glance: U.S. Geological Survey (USGS) 
Established:      1879 
Key Statute:      Organic Act of 1879 (20 Stat. 394) 
Mission:             “To serve  the Nation by providing reliable 
scientific information to describe and understand the Earth; 
minimize  loss of life and property from  natural disasters; 
manage water, biological,  energy, and mineral  resources;  and 
enhance and protect our quality of life.”* 
Leadership:        Director 
Headquarters:   Reston, VA 
Average Staff:    7,900 
Regions:   
                          Unified Regions: 12 (numbered)                           
 
                          Agency Regions: 7 (colored)             
Source:  *USGS, “Who We Are,”  at https://www.usgs.gov/about/about-us/who-we-are.
 
In 1878, the National Academy of Sciences issued a report to Congress asking Congress to 
provide a plan for surveying and mapping the western territories of the United States.99 In 
response, Congress passed an appropriations bil  the following year that authorized the creation of 
the U.S. Geological Survey (USGS). Congress established the USGS for the express purpose of 
overseeing the “classification of the public lands, and examination of the geological structure, 
mineral resources, and products of the national domain.”100 The authorities and responsibilities of 
USGS have shifted and evolved over time, with many of its prior activities leading to the 
formation of new governmental agencies.101 Today, however, USGS serves as the science agency 
of DOI, providing physical and biological information across five mission areas: (1) water 
resources, (2) energy and mineral resources, (3) natural hazards, (4) core science systems, and (5) 
ecosystems.102 Unlike other DOI bureaus, USGS has no regulatory or land management mandate. 
A presidential y appointed director based out of the agency’s headquarters in Reston, VA, 
administers USGS and oversees seven regional directors across the country. In addition to 
regional offices, USGS operates science centers, laboratories, and field offices that monitor, 
assess, and conduct research on a wide range of topics.103 
                                              
99 Rabbitt, 
United States Geological Survey. 
100 Sundry  Civil Expenses bill, passed  on March 3, 1879, 43 U.S.C. §31. 
101 Rabbitt
, United States Geological Survey. T he Bureau of Reclamation, the Office of Surface  Mining Reclamation 
and Enforcement, and the Federal Energy Regulatory Commission are among the modern -day agencies that can trace 
their roots to USGS  and its prior work. 
102 For a more complete discussion  of the history and programs of USGS,  see  CRS  In Focus  IF11433, 
The U.S. 
Geological Survey (USGS): FY2021 Appropriations Process and Background , by Anna E. Normand. T he FY2021 
budget  request  proposed restructuring mission areas and reorganizing programs under mission areas. In the FY2021 
appropriations act, Congress reduced  USGS  mission areas from six to five by eliminating the Land Resources  mission 
area and transferring its programs and funding to other mission areas. 
103 USGS,  “About—Organization,” at https://www.usgs.gov/about/organization. 
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Departmental Offices and Programs104 
DOI has multiple  departmental offices that provide leadership, coordination, and services to the 
department’s various bureaus and programs. These offices coordinate department-wide activities 
and oversee specialized functions under DOI’s jurisdiction not administered directly at the bureau 
level.  
Office of the Secretary 
The Office of the Secretary provides leadership for the entire department through the 
development of policy and through executive oversight of the annual budget and appropriations 
process. The Office of the Secretary also manages the administrative operations of DOI, including 
(but not limited to) financial services, information technology and resources, acquisition, and 
human resources. In addition, the Office of the Secretary manages other department-wide 
programs, offices, and revolving funds, including the following: 
  
Central Hazardous Materials Fund provides remediation services to national 
parks, national wildlife  refuges, and other DOI-managed lands impacted by 
hazardous substances. This remediation process follows the guidelines 
established under the Comprehensive Environmental Response, Compensation, 
and Liability  Act (CERCLA)—also known as the Superfund statute.105
 
  
Natural Resource Damage Assessment and Restoration program coordinates and 
oversees DOI’s restoration efforts for DOI-managed lands impacted by oil spil s 
or the release of hazardous substances. In partnership with federal, state, and 
tribal co-trustees, the program conducts damage assessments, planning, and 
restoration implementation on DOI lands. 
 
  
Office of Natural Resources Revenue (ONRR) is responsible for the collection, 
accounting, and verification of any natural resource and energy revenue 
generated from federal and Indian leases and royalty payments. (See 
“Bureau of 
Ocean Energy Management” section for the history behind ONRR’s creation.)
 
  
Payments in Lieu of Taxes (PILT) program makes payments to approximately 
1,900 local government units across the United States and its insular areas where 
certain federal lands are located. The PILT payments are intended to help offset 
the loss in property taxes to local governments caused by the presence of federal 
lands, which largely are exempt from taxation.106
 
  
Wildland Fire Management program is responsible for addressing wildfires on 
public lands. The program comprises of the Office of Wildland Fire and the four 
                                              
104 T his section does not represent all DOI divisions and programs. Instead, it reflects the offices and programs included 
as discrete line items under the Departmental Offices and Department -Wide Programs accounts funded through the 
annual Interior, Environment, and Related Agencies appropriations bill (see 
“ Overview of DOI Appropriations” section 
for more information). OST  is discussed  here; however, FY2021 appropriations were requested and provided as part of 
the Indian Affairs account. Prior to FY2021, appropriations for (OST  typically were provided as part of the 
Departmental Offices account. 
105 Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA)  of 1980, P.L. 96-510, 
approved December 11, 1980. 42 U.S.C. §§9601 et seq.  For a more complete discussion  of CERCLA,  see CRS  Report 
R41039, 
Com prehensive Environm ental Response, Co m pensation, and Liability Act: A Sum m ary of Superfund Cleanup 
Authorities and Related Provisions of the Act, by David  M. Bearden. 
106 For a more complete discussion  of the Payments in Lieu of T axes program , see CRS  Report R46260, 
The Payments 
in Lieu of Taxes (PILT) Program : An Overview,  by R. Eliot Crafton. 
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DOI land management bureaus with wildland fire management responsibilities 
(BIA, BLM,  FWS, and NPS).107 
  
Working Capital Fund (WCF) is a revolving fund that finances centralized 
administrative services and systems to DOI bureaus and offices.108 The WCF 
aims to reduce duplicative systems and staff across DOI; it provides financing for 
centralized functions that provide payroll, accounting, information technology, 
and other support services. 
 
Office of the Solicitor 
In 1946, Congress established the Office of the Solicitor to provide advice, counsel, and legal 
representation to DOI.109 To accomplish this work, the Office of the Solicitor employs more than 
500 employees, 400 of whom are licensed attorneys.110 The Office of the Solicitor is organized 
into the Immediate Office of the Solicitor, the Departmental Ethics Office, the Departmental 
FOIA (Freedom of Information Act) Office, the Indian Trust Litigation Office, six legal divisions, 
an administrative division, and eight regional offices.111 
Office of the Inspector General 
In 1978, Congress established inspector general positions and offices in more than a dozen 
specific departments and agencies, including DOI.112 The mission of the Office of the Inspector 
General (OIG) is to provide independent oversight and accountability to the department’s 
programs, operations, and management. In addition to the Immediate Office of the Inspector 
General, the OIG has five offices: the Office of Management; the Office of Investigations; the 
Office of Audits, Inspections, and Evaluations; the Office of General Counsel; and the Office of 
Strategic Programs.113 The OIG operates from a headquarters office in Washington, DC, and 
regional offices located in Herndon, VA; Atlanta, GA; Lakewood, CO; Bil ings,  MT; and 
Sacramento, CA.114 
Bureau of Trust Funds Administration (Office of the Special Trustee for 
American Indians) 
The status and operation of the Office of Special Trustee for American Indians (OST has been an 
issue of congressional interest in recent years. According to DOI, the Bureau of Trust Funds 
Administration  (BTFA) currently performs the functions of the OST.115 The American Indian 
                                              
107 Reclamation also has limited responsibility to manage land  under its jurisdiction for wildfires.  For a more complete 
discussion  of federal wildfire  programs, see  CRS  In Focus  IF10732, 
Federal Assistance for Wildfire  Response and 
Recovery, by  Katie Hoover. 
108 43 U.S.C.  §1467 authorized the creation of the working capital fund in the Department of the Interior. 
109 43 U.S.C.  §1455, June 26, 1946, ch. 494, 60 Stat. 312. 
110 Statement taken from the Office of the Solicitor website at https://www.doi.gov/solicitor (accessed  February  3, 
2021). 
111 Office of the Solicitor, “ About the Office of the Solicitor,” at https://www.doi.gov/solicitor/about (May 2021).  
112 Inspector General Act of 1978, 92 Stat. 1101, P.L. 95-452. 
113 DOI, Office of the Inspector General, “ OIG Offices,” at https://www.doioig.gov/about-us/oig-offices. 
114 DOI, Office of the Inspector General, “ Contact Us,” at https://www.doioig.gov/contact-us. 
115 Personal communication between CRS  and DOI Office of Legislative Affairs, April 27, 2021. 
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Trust Fund Management Reform Act established the OST in 1994.116 The OST provided fiduciary 
oversight and management of the more than 55 mil ion  surface acres and 59 mil ion subsurface 
mineral acres of tribal assets held in trust by the federal government.117 The office carried out its 
mission from a national office in Washington, DC, and through five regional offices across the 
nation.118 On October 1, 2020, DOI transferred many of the trust responsibilities performed by the 
OST to a newly established BTFA, pursuant to S.O. 3384. DOI considers the BTFA operational; 
however, Congress has expressed concerns regarding the creation of the BTFA (see 
“Recent DOI 
Reorganization Plans, Proposals, and Issues for Congress” for more information). For the 
purposes of this report, CRS has treated the establishment of the BTFA as operational. 
Office of Insular Affairs 
The United States acquired its first insular territories in 1898 with the annexation of the Hawai an 
Islands and the acquisition of Puerto Rico, Guam, and the Philippines from Spain following the 
Spanish-American War.119 For much of the early 20th century, territorial oversight of these new 
possessions fel  largely to the War Department. In 1934, President Franklin D. Roosevelt created 
the Division of Territories and Island Possessions to centralize responsibility for coordinating 
oversight of the nation’s insular regions.120 The division—now known as the Office of Insular 
Affairs—currently administers federal oversight of American Samoa, Guam, the U.S. Virgin 
Islands, and the Commonwealth of the Northern Mariana Islands, with the goal of promoting their 
economic, social, and political development.121 The office also administers federal assistance and 
U.S. economic commitments to the Freely Associated States: the Federated States of Micronesia, 
the Republic of the Marshal  Islands, and the Republic of Palau.122 
DOI Employment Levels 
In 2020, the average number of employees working for DOI was 63,175, according to OPM. (See 
Table 1.)123 The data reflect 
on-board employment figures, which are based on the number of 
employees in pay status at the end of the quarter. Data are published on a quarterly basis (March, 
June, September, and December). Data in this report reflect December 2020 figures, unless 
                                              
116 P.L. 103-412, 108 Stat 4239. 
117 Bureau  of T rust Funds  Administration (BT FA), “About Us,” at https://www.doi.gov/ost/about_us  (accessed  on 
February 4, 2021). T he DOI website refers to the OST  as  the BT FA.  
118 OST , “OST  Organization Chart ” at https://www.doi.gov/sites/doi.gov/files/uploads/ost_org_chart_08-03-
17_revised.pdf.  
119
 Utley and Mackintosh, 
Department of Everything Else.
 
120 Executive Order 6726, “Establishing the Division of T erritories and Island Possessions in the Department of the 
Interior and T ransferring T hereto the Functions of the Bureau of Insular Affairs, War Department, Pertaining to the 
Administration of the Government of Puerto Rico,” May 29, 1934. 
121 Office of Insular Affairs, 
Budget Justifications and Performance Information Fiscal Year 2021, at 
https://www.doi.gov/sites/doi.gov/files/uploads/oia-2021-greenbook-final.pdf.  
122 Under the Compacts of Free Association, the Freely Associated States (FAS)  are considered  sovereign nations 
whose  citizens are eligible  for various U.S.  federal programs and services in exchange for full international defense 
authority by the United States. For a more complete discussion  of FAS  policies, see CRS  Report R44753, 
The Pacific 
Islands: Policy Issues, by T homas Lum and Bruce  Vaughn. 
123 OPM is an independent agency that functions as the central human resources department of the executive branch 
and is a primary source for data and information regarding DOI employment figures—as well  as the entire federal 
workforce. For a more complete discussion  of OPM data, see CRS  Report R43590, Federal Workforce Statistics 
Sources:  OPM and OMB, by Julie  Jennings and Jared  C. Nagel. 
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otherwise specified. Because OPM data include full-time, part-time, and seasonal staff, 
employment totals tend to spike during the summer months, when agencies such as NPS and 
BLM increase their seasonal workforce.  
OPM figures differ from DOI Budget Office data. The DOI Budget Office calculates employment 
by full-time equivalents, defined as the total number of regular straight-time hours (not including 
overtime or holiday hours) worked by employees, divided by the number of compensable hours 
applicable to each fiscal year.124 
Table 1. DOI Employment Trends, by Agency 
(on-board employment totals) 
Average 
Agency 
Mar. 2020 
June 2020 
Sep. 2020 
Dec. 2020 
2020  
Bureau of Land Management 
8,838 
10,713 
10,540 
8,887 
9,745 
Bureau of Ocean Energy 
Management 
562 
563 
571 
574 
568 
Bureau of Reclamation 
5,319 
5,339 
5,350 
5,306 
5,329 
Bureau of Safety & Environmental 
Enforcement 
758 
768 
768 
777 
768 
Indian Affairs 
7,115 
7,180 
7,138 
7,040 
7,118 
National Park Service 
16,744 
20,971 
20,785 
17,069 
18,892 
Office of the Inspector General 
259 
261 
268 
265 
263 
Office of the Secretary of the 
Interior 
3,393 
3,418 
3,411 
3,446 
3,417 
Office of the Solicitor 
493 
494 
516 
529 
508 
Office of Surface Mining 
348 
351 
356 
353 
352 
Reclamation & Enforcement 
U.S. Fish & Wildlife  Service 
8,103 
8,291 
8,414 
8,399 
8,302 
U.S. Geological  Survey 
7,802 
7,868 
7,996 
7,989 
7,914 
Total—Department  of the 
Interior 
59,734 
66,217 
66,113 
60,634 
63,175 
Source: U.S. Office of Personnel  Management (OPM), FedScope database, Employment cubes, Cabinet-Level 
Agencies  parameter set to Department of the Interior, at https://www.fedscope.opm.gov/.  Data accessed from 
FedScope on April 14, 2021. 
Notes: Numbers reflect employees  on board (in a pay status). Figures may not add up to totals shown due to 
rounding. “Indian Affairs” includes the Bureau of Indian Affairs  (BIA) and the Bureau of Indian Education (BIE). 
Per information provided to CRS from DOI, “Office of the Secretary of the Interior” includes employees  from 
the Office of Insular Affairs,  Office of the Special Trustee for American  Indians, and the various Assistant 
Secretary Offices that oversee  DOI bureaus and agencies.  
The OPM Fedscope data presented i
n  Table  1 are available  by location  of employment  for 
each bureau and office reflected.
 Table  2 shows DOI employment  figures both within  and 
outside  of the “District of Columbia”  location  parameter. OPM defines  “Location”  as the 
                                              
124 For comparison, the FY2021 
Interior Budget in Brief (Appendix H) estimated employment of 60,939 full-time 
equivalents (FT Es) for FY2021 and 61,593 FT Es in FY2019.  
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official  duty station of an employee;125  this does not capture the number of employees  who 
may work in the greater Washington, DC, metropolitan  area or at DOI agency headquarters 
locations in the surrounding region.126 For example, FWS staff working from the agency’s 
headquarters in Fal s Church, VA, are not counted under the District of Columbia “Location” 
parameter. 
Table 2. DOI Employment: Inside vs. Outside Washington, DC 
(as of December 2020) 
Total 
Agency 
Inside DC  
Outside  DC  
Employment 
% Inside DC  
Bureau of Land Management 
85 
8,802 
8,887 
1% 
Bureau of Ocean Energy Management 
35 
539 
574 
6% 
Bureau of Reclamation 
46 
5,260 
5,306 
1% 
Bureau of Safety & Environmental 
Enforcement 
34 
743 
777 
4% 
Indian Affairs 
64 
6,976 
7,040 
1% 
National Park Service 
1,017 
16,052 
17,069 
6% 
Office of the Inspector General 
32 
233 
265 
12% 
Office of the Secretary of the Interior 
754 
2,692 
3,446 
22% 
Office of the Solicitor 
242 
287 
529 
46% 
Office of Surface Mining Reclamation & 
Enforcement 
75 
278 
353 
21% 
U.S. Fish & Wildlife  Service 
23 
8,376 
8,399 
<1% 
U.S. Geological  Survey 
6 
7,983 
7,989 
<1% 
Total—Department  of the 
Interior 
2,413 
58,219 
60,634 
4% 
Source: OPM, FedScope database, Employment Trend cubes, Cabinet-Level Agencies parameter  set to 
Department of the Interior,  at https://www.fedscope.opm.gov/.  Data accessed from  FedScope on April 14, 2021. 
Notes: Data
 reflect places of employment  for DOI staff, not places of residence.  “Indian Affairs” includes the 
Bureau of Indian Affairs (BIA) and the Bureau of Indian Education (BIE). Per information provided to CRS from 
DOI, “Office of the Secretary of the Interior” includes employees  from  the Office of Insular Affairs,  Office of the 
Special Trustee for American  Indians, and the various Assistant Secretary  Offices that oversee  DOI bureaus and 
agencies.
 
                                              125 OPM, Fedscope, “Data Definitions,” at https://www.fedscope.opm.gov/datadefn/index.asp, accessed  on December 
8, 2020. 
126 A 2019 version of this CRS  report included  DOI employment figures in what OPM referred to as the “DC core-
based  statistical area (CBSA).”  OPM defined  a CBSA  as “a geographic area having at least one urban area of 
population, plus adjacent territory that has a high degree  of social and economic integration with the core as measured 
by commut ing ties.”126 OPM no longer reports on employment figures within the DC CBSA.  Largely as a result of this 
change, figures  in this report for “Inside DC” are lower than those for “Inside DC CBSA”  published  in the 2019  report.  
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Overview of DOI Appropriations
U.S. Department of the Interior: An Overview 
 
Overview of DOI Appropriations 
Discretionary funding for DOI is provided primarily through Title I of the annual Interior, 
Environment, and Related Agencies appropriations bil .127 The Bureau of Reclamation 
(Reclamation) and the Central Utah Project, however, receive funding through the Energy and 
Water Development appropriations bil .128  Several of the agencies that receive discretionary funds 
through these two appropriations bil s also receive mandatory funding under various authorizing 
statutes.  
DOI Discretionary Appropriations: FY2017-FY2021129 
Figure 4 shows the budget trends for both the Interior and the Energy and Water appropriations 
bil s over the past five fiscal years (FY2017-FY2021). From FY2017 to FY2021, total DOI 
appropriations increased 13% in current dollars.130 Total appropriations including supplemental 
appropriations fluctuated from FY2017 to FY2021. If supplemental appropriations are not 
considered, DOI discretionary appropriations increased each year from FY2017 to FY2020. 
Regular discretionary appropriations decreased by roughly 1% from FY2020 to FY2021 and by 
more than 5% including supplemental appropriations. 
Figure 4. DOI Discretionary Appropriations: FY2017-FY2021 
(in current dol ars) 
 
Source: CRS, with data from the annual 
Interior Budget in Brief for FY2019-FY2021. Figures for each of FY2017-
FY2019 were taken from the volume  published two years fol owing the fiscal year in question (e.g., for FY2017, 
                                              
127 Hereinafter, the annual Interior, Environment, and Related Agencies  appropriations bill is  referred to as the Interior 
appropriations bill. 
128 T he Central Utah Project  (CUP) is a federal water storage project originally authorized under the management of 
Reclamation, although it  is now overseen and administered by a separate office within DOI .  
129 For more in-depth information on DOI appropriations, see CRS  Report R46519, 
Interior, Environment, and Related 
Agencies: Overview  of FY2021 Appropriations, by Carol Hardy Vincent  and CRS  Report R46384, 
Energy and Water 
Developm ent: FY2021 Appropriations, by Mark Holt and Corrie E. Clark.  
130 Amounts in this section reflect current dollars. Using inflation-adjusted (constant) dollars would  result in different 
amounts of change during  this five-year period. 
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U.S. Department of the Interior: An Overview 
 
figures are from FY2019 document). FY2020 figures reflect enacted totals taken from  H.Rept. 116-449 and 
H.Rept. 116-448. Supplemental figures taken from P.L. 116-136 and P.L. 116-113. FY2021 figures reflect enacted 
totals taken from  P.L. 116-260. 
Notes: Actual totals include rescissions  and transfers authorized by the Interior, Environment, and Related 
Agencies  and the Energy and Water Development  appropriations bil s.  Figures reflect Emergency Supplemental 
Appropriations for FY2018 and FY2019. For FY2018 this includes $50 mil ion  enacted as part of the Additional 
Supplemental Appropriations for Disaster  Relief Requirements  Act, 2017 (P.L. 115-72), and $516 mil ion  enacted 
as part of the Further Additional Supplemental Appropriations  for Disaster  Relief  Requirements Act, 2018 ( P.L. 
115-123, Division B, Subdivision I). For FY2019, this reflects  $327.8 mil ion  in funding provided as part of the 
Additional Supplemental Appropriations for Disaster  Relief Act, 2019 (P.L. 116-20). For FY2020, this reflects $4 
mil ion  in funding provided to the U.S. Fish and Wildlife  Service  as part of the U.S.-Mexico-Canada Agreement 
Implementation Act (P.L. 116-113) and funding provided as part of the Coronavirus Aid, Relief,  and Economic 
Security Act or the ‘ CARES Act” (P.L. 116-136). The CARES Act contained $756 mil ion  for various activities of 
the Bureau of Indian Affairs ($453 mil ion); the Bureau of Indian Education ($69 mil ion);  the Office of the 
Secretary ($158.4); the Office of Insular Affairs  ($55 mil ion);  and the Bureau of Reclamation ($20.6 mil ion). 
DOI Discretionary Appropriations: FY2021, by Agency 
Figure 5 shows the breakdown of enacted FY2021 appropriations for DOI bureaus, offices, and 
programs funded through the Interior and the Energy and Water appropriations bil s. Figures are 
presented in total dollars (in mil ions) and as percentages of the department’s $15.4 bil ion in 
enacted appropriations for FY2021. 
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 U.S. Department of the Interior: An Overview 
 
Figure 5. DOI Discretionary Appropriations for FY2021, by Agency
U.S. Department of the Interior: An Overview 
 
Figure 5. DOI Discretionary Appropriations for FY2021, by Agency 
(in mil ions) 
 
Source: FY2021 figures reflect enacted totals taken from  the Joint Explanatory Text of P.L.  116-260.  
Notes: Figures may not add to total shown due to rounding. “Indian Affairs” includes funding for the Bureau of 
Indian Affairs (BIA), the Bureau of Indian Education (BIE), and the Office of the Special Trustee (OST); 
“Departmental Offices” includes funding for the Office of the Secretary,  Insular Affairs,  Office of the Solicitor, 
and the Office of Inspector General;  “Department-Wide Programs”  includes funding for Wildlife  Fire 
Management, Central Hazardous Materials Fund, Natural Resource Damage Assessment  Fund, Working Capital 
Fund, and Payments in Lieu of Taxes (PILT; which was funded in the General Provisions  of Title I of the FY2021 
appropriations law). Additional abbreviations are (clockwise):  Bureau of Ocean Energy Management (BOEM), 
Bureau of Safety and Environmental Enforcement (BSEE), National Park Service  (NPS), Bureau of Reclamation 
(Reclamation), U.S. Fish and Wildlife  Service  (FWS), U.S. Geological  Survey (USGS), Bureau of Land Management 
(BLM), and Office of Surface Mining Reclamation and Enforcement (OSMRE). 
 
Author Information 
 Mark K. DeSantis 
   
Analyst in Natural Resources Policy     
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U.S. Department of the Interior: An Overview 
 
 
Key Policy Staff 
Area of Expertise 
Name 
Bureau of Land Management 
Carol Hardy-Vincent 
Bureau of Ocean Energy Management 
Laura B. Comay  
Bureau of Reclamation 
Charles V. Stern 
Bureau of Safety and Environmental Enforcement 
Laura B. Comay 
Bureau of Indian Affairs 
Tana Fitzpatrick 
Bureau of Indian Education 
Cassandria Dortch 
National Park Service 
Laura B. Comay / Mark K. DeSantis 
Office of Surface Mining Reclamation and Enforcement 
Lance N. Larson 
U.S. Fish and Wildlife  Service 
R. Eliot Crafton 
U.S. Geological  Survey 
Anna E. Normand 
 
 
Disclaimer 
This document was prepared by the Congressional Research Service (CRS). CRS serves as nonpartisan 
shared staff to congressional committees and Members of Congress. It operates solely at the behest of and 
under the direction of Congress. Information in a CRS Report should n ot be relied upon for purposes other 
than public understanding of information that has been provided by CRS to Members of Congress in 
connection with CRS’s institutional role. CRS Reports, as a work of the United States Government, are not 
subject to copyright protection in the United States. Any CRS Report may be reproduced and distributed in 
its entirety without permission from CRS. However, as a CRS Report may include copyrighted images or 
material from a third party, you may need to obtain the permission of the copyright holder if you wish to 
copy or otherwise use copyrighted material. 
 
Congressional Research Service  
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