A letter report issued by the Government Accountability Office with an abstract that begins "The Department of Defense (DOD) relies on thousands of suppliers to provide weapons, equipment, and raw materials to meet U.S. national security objectives. Yet, increased globalization in the defense industry and consolidation of the defense supplier base into a few prime contractors has reduced competition and single-source suppliers have become more common for components and subsystems. For this report, GAO (1) assessed DOD's efforts to monitor the health of its defense supplier base, and (2) determined how DOD identifies and addresses gaps that might exist in its supplier base. To conduct its work, GAO reviewed supplier-base-related laws, regulations, and guidelines; met with officials from DOD's Office of Industrial Policy, defense contractors, and other DOD officials; and surveyed 20 major DOD weapon acquisition program officials on potential supplier-base gaps."