The Department of Defense (DOD) reported shortages of approximately 2,000 pilots at the end of fiscal year 1998 and projected that shortages would continue for several years. Retaining qualified pilots is important not only to ensure that operational requirements can be met, but also to recoup the substantial investments the services make in training their pilots. Concerned about reports of pilot shortages, the Chairman and former Ranking Minority Member of the Subcommittee on Military Personnel, House Committee on Armed Services, asked GAO to review and identify reasons for the reported pilot shortages and offer solutions to address the issue. Specifically, GAO determined (1) the services' reported and projected estimates of their pilot shortages, (2) the basis for the services' pilot requirements, (3) key factors that account for the reported pilot shortages, and (4) concerns that are causing pilots to consider leaving the military.