The serious incident of April 2001 between the United States and the People's Republic of China (PRC) involved a collision over the South China Sea between a U.S. Navy EP-3 reconnaissance plane and a People's Liberation Army (PLA) naval F-8 fighter that crashed. After surviving the near-fatal accident, the U.S. crew made an emergency landing of their damaged plane onto the PLA's Lingshui airfield on Hainan Island, and the PRC detained the 24 crew members for 11 days. Washington and Beijing disagreed over the cause of the accident, the release of the crew and plane, whether Washington would "apologize," and the PRC's right to inspect the EP-3. In the longer term, the incident has implications for the right of U.S. and other nations' aircraft to fly in international airspace near China. (This CRS Report, first issued on April 20, 2001, includes an update on the later EP-3 recovery.) The incident prompted assessments about PRC leaders, their hardline position, and their claims. While some speculated about PLA dominance, President and Central Military Commission Chairman Jiang Zemin and his diplomats were in the lead, while PLA leaders followed in stance with no more inflammatory rhetoric. Still, the PLA is likely to benefit from this incident. Despite PRC claims that the EP-3 plane caused the accident, it appears that the PLA pilot, executing a close pass in an apparent attempt to impress or intimidate the EP-3 crew, made a fatal error in judgment. International law is clear that all aircraft have a right of overflight with respect to ocean areas beyond the territorial sea (past 12 miles out). There are implications for U.S. policy toward the PRC and Taiwan, and defense policy. This incident of April 2001 is the third in a series of major troubling difficulties since the mid-1990s that could have serious implications for U.S.-PRC relations. The standoff raised questions about whether the issues of the incident and arms sales to Taiwan should be linked and whether to change the process of annual arms sales talks with Taipei. A further worsening of political ties could negatively affect the business climate in China for U.S. firms and disrupt negotiations over China's WTO accession. Airborne reconnaissance remains a vital component of intelligence collection for military and other national security purposes. Observers speculate that the chief benefit to the PRC from inspecting the EP-3 would be to gather information about U.S. targets and degree of success that could enable them to prepare countermeasures to hinder future U.S. surveillance efforts. The incident has potential implications for U.S. military surveillance operations in at least four areas: operational strain on the EP-3 fleet, conditions for conducting airborne surveillance missions in the future, the need for escorts or other protective forces, and using unmanned air vehicles (UAVs) for airborne surveillance missions. There are also implications for U.S. relations with allies and others. Japan seems increasingly concerned about PRC assertiveness. South Korea is concerned that a major deterioration in U.S.-China relations could undermine its "sunshine policy" of engaging North Korea. The incident may add to Manila's desire to revive its security ties with Washington. Australia has concerns. Moscow's relatively restrained public response to the incident is surprising and noteworthy.