The Department of Energy's (Department) Albuquerque Operations Office (Albuquerque) owns seven aircraft that support defense programs, research and development efforts, emergency response programs, and official travel of Government and contractor employees. An Office of Inspector General (OIG) report, issued in 1994, identified concerns with Albuquerque's cost for air service. Since that report, there have been reductions in cost and personnel indicating changes in air service requirements. We conducted this audit to determine (1) whether costs to operate Albuquerque's aircraft were excessive and (2) if individual aircraft in the fleet were justified. On January 7, 1999, the OIG issued a separate report on its Review of the U.S. Department of Energy’s Aircraft Activities, (DOE/IG-0435). This report assessed aircraft operations nationwide, and suggested that enhanced centralized management was needed to ensure that new and existing aircraft were justified based on mission needs, and that program costs were minimized.