The Spacelab program was a unique endeavor. For the first time in the history of the United States space effort, the design and development of a major element of a manned space vehicle was entrusted to a foreign agency and to a group of countries which had never before built such a system. This book tells of this cooperative effort between the National Aeronautics and Space Administration (NASA) and the European Space Agency (ESA) from the program's inception until the delivery of hardware to the United States. This chronological history of the Spacelab project includes chapters on "Building an International Agreement, 1969-1973"; "Birth of a Concept, 1960-1973"; "Getting Under Way, 1973-1974"; "Solidifying the Requirements, 1973-1976"; "Planning for Spacelab Use, 1973-1977";"Reviews, Reviews, Reviews, 1975-1978"; "At Last--Hardware!, 1976-1979"; "Off the Mainstream, 1974-1984"; "Integration and Acceptance, 1978-1982"; Readiness for Flight, 1979-1983"; "At Long Last--Spacelab Flies!, 1983-1985"; and "Lessons Learned." Appendices include "Memorandum of Understanding"; "Joint Programme Plan"; "Programme Requirements"; Key Program Participants"; and an extensive source list. This book, and the original documents it represents, constitutes basic historical source material for the study of the U.S. manned spaceflight program and for Spacelab in particular. (CW)