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Updated February 22, 2024
Defense Primer: Under Secretary of Defense for Research and
Engineering
Advances in science and technology have long played a
Furthermore, in the conference report (H.Rept. 114-840) for
critical role in ensuring the technological preeminence of
the FY2017 NDAA, the conferees stated their expectation
the United States military. For this reason, the Department
that the USD (R&E) “would take risks, press the
of Defense (DOD) is the largest funder of federal research
technology envelope, test and experiment, and have the
and development. The Under Secretary of Defense for
latitude to fail, as appropriate.”
Research and Engineering (USD (R&E)) is a civilian
official reporting directly to the Secretary of Defense. The
Roles and Responsibilities of the USD
USD (R&E) serves as the principal advisor to the Secretary
(R&E)
of Defense for DOD research, engineering, and technology
The powers and duties of the USD (R&E) include
development activities and programs.
• serving as the chief technology officer (CTO) of DOD
Over the last several years, policymakers and others have
with the mission of advancing technology and
expressed concern that the long-held technological edge of
innovation for the military services and DOD;
the U.S. military is eroding due, in part, to the proliferation
• establishing policies on, and supervising all defense
of technologies outside the defense sector, organizational
research and engineering, technology development,
and cultural barriers to DOD effectively incorporating and
technology transition, appropriate prototyping activities,
exploiting commercial innovations, and insufficient
experimentation, and developmental testing activities
engagement with leading-edge companies that have not
and programs, and unifying defense research and
historically been a part of the DOD innovation system. The
engineering efforts across DOD; and
position of the USD (R&E) as the third highest ranking
• serving as the principal advisor to the Secretary of
DOD official—behind the Secretary and Deputy
Defense on all research, engineering, and technology
Secretary—is intended to promote faster innovation and to
development activities and programs in DOD.
increase risk-tolerance in the pursuit of new technologies.
Department of Defense Directive (DODD) 5137.02
Origin of the USD (R&E) Position
specifies 45 key functions and responsibilities of the USD
(R&E) and defines the authorities of the USD (R&E) and
Leadership of DOD research, engineering, and technology
his or her relationships with other senior DOD officials.
development activities and functions within the Office of
The responsibilities detailed in DODD 5137.02 include
the Secretary of Defense (OSD) have varied over the course
of DOD’s his
managing the DOD science and technology (S&T) portfolio
tory. For example, there was a USD (R&E)
to address near-term and far-term capability gaps against
from 1977 to 1986. Reestablishment of the position of the
emerging threats and ensuring that DOD technical
USD (R&E) in 2016 through the National Defense
infrastructure, scientific and engineering capabilities, and
Authorization Act for Fiscal Year 2017 (FY2017 NDAA,
associated resources align with DOD priorities.
P.L. 114-328) represents the most recent realignment.
In the FY2022 NDAA (S. 1605), Congress designated the
Specifically, P.L. 114-328 eliminated the position of the
USD (R&E) as the Chief Technical Advisor to the Joint
Under Secretary of Defense for Acquisition, Technology,
Requirements Oversight Council (JROC) with the intent of
and Logistics (USD (AT&L)) and established the positions
assisting DOD “in taking full advantage of technological
of USD (R&E) and the Under Secretary of Defense for
possibilities, on-ramping new technologies into military
Acquisition and Sustainment (USD (A&S)).
operations, and identifying new, affordable, and effective
In reestablishing the position of USD (R&E) the Senate
means of achieving military ends.” S. 1605 also required an
Armed Services Committee stated (S.Rept. 114-255)
independent study and report to Congress on the role of the
USD (R&E) in the JROC, including possible adjustments.
The committee expects that just as previous USD
(R&E) incumbents led the so-called “Second
Organizational Structure of the OUSD
Offset” strategy, which successfully enabled the
(R&E)
United States to leap ahead of the Soviet Union in
The organizational and management structure of the office
terms of military technology, the new USD (R&E)
of the USD (R&E) (OUSD (R&E)) has evolved numerous
would be tasked with driving the key technologies
times from the original structure proposed in a 2017 DOD
that must encompass what defense leaders are now
report to Congress and from the structure approved by the
calling a “Third Offset” strategy: cyber and space
Deputy Secretary of Defense in a memorandum dated July
capabilities, unmanned systems, directed energy,
13, 2018. As shown in Figure 1, currently, the OUSD
undersea warfare, hypersonics, and robotics, among
(R&E) has three main subcomponents:
others.
https://crsreports.congress.gov
Defense Primer: Under Secretary of Defense for Research and Engineering
• Assistant Secretary for S&T responsible for oversight of
fast pace many expect is needed to maintain the U.S.
DOD’s S&T enterprise, including its S&T workforce
technological lead over potential adversaries.
and laboratory infrastructure; management and
Some have expressed concerns that dividing the roles and
administration of a broad portfolio of S&T programs,
responsibilities of the USD (AT&L) into an USD (R&E)
including basic research, the Small Business Innovation
and an USD (A&S) will exacerbate the valley of death (i.e.,
Research and Small Business Technology Transfer
the barriers and challenges that exist in bringing a new
programs, and DOD’s Manufacturing Innovation
technology from the research laboratory to full scale
Institutes; and efforts related to technology and program
deployment in the armed forces).
protection.
• Assistant Secretary for Critical Technologies
In the conference report (H.Rept. 114-840) for the FY2017
responsible for managing the capability analysis and
NDAA, the conferees acknowledged the potential
investments for DOD’s 11 critical technologies which
challenges that exist in separating the roles and
include 5G; advanced computing and software; directed
responsibilities of the USD (AT&L) into the positions of a
energy; human-machine interfaces; hypersonics;
USD (R&E) and a USD (A&S). However, the conference
integrated network systems-of-systems; integrated
report asserts that elevating the missions of advancing
sensing and cyber; microelectronics; renewable energy
technology and innovation within DOD, fostering distinct
generation and storage; space technology; and trusted
technology and acquisition cultures to better deliver
artificial intelligence and autonomy.
superior capabilities, and providing greater oversight and
• Assistant Secretary for Mission Capabilities responsible
management of DOD components outside the military
for identifying, incubating, and transitioning
services would best be addressed by the creation of two
technologies, systems, and system of systems that close
undersecretaries. Furthermore, the conferees indicated that
time-critical gaps in high-priority, multi-component
any potential barriers or gaps could “be mitigated through
missions to maintain United States’ technological
effective leadership and management.”
superiority.
In an effort to bridge gaps between the two offices, DODD
In addition, a number of agencies within DOD’s research
5137.02 details their relationship, including requiring the
and engineering enterprise are overseen by the OUSD
USD (R&E) to advise the USD (A&S) on materiel
(R&E). Specifically, the Defense Advanced Research
development, milestone, and production decisions.
Projects Agency, the Office of Strategic Capital, the Missile
Defense Agency, and the Space Development Agency
Relevant Statutes
report to the USD (R&E).
Title 10, U.S. Code, Chapter 4—Office of the Secretary of
Defense
USD (R&E) and USD (A&S) Relationship
CRS Products
A wide range of observers see a close and cooperative
CRS In Focus IF10553, Defense Primer: RDT&E.
relationship between the USD (R&E) and the USD (A&S)
CRS Report R45403, The Global Research and Development
as critical for the efficient and effective delivery of
Landscape and Implications for the Department of Defense.
advanced technologies to the warfighter, especially at the
Figure 1. Organizational Chart for Office of USD (R&E)
Sources: Adapted from https://www.cto.mil/leadership/ (accessed on February 22, 2024).
Notes: This represents a simplified version of the organizational structure of the OUSD (R&E). OSC = Office of Strategic Capital; MDA =
Missile Defense Agency; DARPA = Defense Advanced Research Projects Agency; SDA = Space Developmental Agency. MDA, DARPA, and
SDA are distinct and separate DOD agencies that report to the USD (R&E). Others are whol y within the OUSD (R&E).
IF10834
Marcy E. Gallo, Analyst in Science and Technology Policy
https://crsreports.congress.gov
Defense Primer: Under Secretary of Defense for Research and Engineering
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https://crsreports.congress.gov | IF10834 · VERSION 12 · UPDATED