This manuscript is a study of the United States Air Force in space. Of all the military services, the Air Force has been preeminently involved for the past fifty years in initiating, developing, and applying the technology of space-based systems in support of the nation's national security. Yet there has been no single-volume overview of the Air Force space story to serve as an introduction and guide for interested readers. This book tells the story of the origins and development of the United States Air Force's space program from its earliest beginnings in the post Second World War period to its emergence as a critical operational presence in the Persian Gulf War.