US Military Uses of Space, 1946-1991 is a themed microfilm collection which presents an integrated record of US military space organisations, operations, and policy from 1945 to 1991. Included are memoranda, messages, presidential decision documents, program management directives, histories, organisational manuals, reports, and studies. Documents concern four basic areas of US space military activity: military support systems (communications, meteorology, reconnaissance and other satellites), space weaponry (anti-satellite weapons and the Strategic Defense Initiative), policy, and organisation. Material concerning military support systems includes papers relating to the establishment of a US photographic reconnaissance satellite program, 1956; US Air Force contracts to Lockheed Missile Systems Division to develop the WS-117L air reconnaissance satellite, 1956-57; the development of the US Air Force reconnaissance satellite, codenamed SENTRY and then SAMOS, 1958; the Central Intelligence Agency (CIA) research and development of an imaging satellite, codenamed CORONA, 1958; launching of CORONA satellite, 18 Aug 1960; the development and launch of Global Positioning Systems (GPS) and Defense Support Program (DSP) satellites designed to provide nuclear explosion detection data relevant to military intelligence collection, treaty verification (Limited Test Ban Treaty, Threshold Ban Treaty, Non-Proliferation Treaty, and Outer Space Treaty), and damage assessment, 1963-1970; development and launch of signals intelligence (SIGINT) satellites, including the RHYOLITE communications satellite, 1970; the launch of the KH-11 electro-optical 'pixel' imaging satellite, Dec 1976; development and launch of ocean surveillance PARCAE satellites, 1976-1989; communications intelligence (COMINT) satellite including the VORTEX and MAGNUM satellites, 1978-1985; the launch of synthetic aperture radar system LACROSSE satellites, 1988-1991; the development and launch of early warning satellites including the Missile Defense Alarm System (MIDAS) to monitor the missile launches from the Eurasian land mass and Submarine- Launched Ballistic Missiles (SLBMs); papers relating to launch systems, including expendable launch vehicles (ELVs), such as modified Martin SM-68 Titan Inter- Continental Ballistic Missiles (ICBMs). Material concerning space weaponry includes Massachusetts Institute of Technology report to US Congress, Office of Technology Assessment, introducing theoretical and scientific concepts for a laser weapons missile defence program, 1984; reports from the US Department of Defense, Strategic Defense Initiative Organization, to the US Congress relating to the costs of a laser and kinetic energy anti-ballistic missile program and its proposed compliance with the 26 May 1972 Anti-Ballistic Missile Treaty, 1984-1990; report from the US Department of Defense, Strategic Defense Initiative Organization, to the US Congress outlining the goals, objectives, and costs of the Strategic Defense Initiative (SDI), 1985; reports from the US General Accounting Office relating to the SDI concept change from laser and kinetic energy weapons to 'Brilliant Pebbles' weaponry, in which several thousand satellite interceptors would orbit the earth having the capability to destroy missile targets, 1990-1991. Documents relating to US military space policy include reports from the US National Security Council outlining the significance of space with respect to US national security, 1958-1985; memoranda from the US Department of Defense urging military priorities for space research, 1959-1977. Material relating to the organisational command of the military space program includes function manuals and inter-agency memoranda detailing the structure and role of specific organisations such as US Aerospace Command, the US Department of Defense, US Air Force Space Command, the Central Intelligence Agency, the Strategic Defense Initiative Organization, the US Army Space Agency, and the US National Aeronautics and Space Administration (NASA).