Spacelab is a facility which enables scientists and engineers to go into space for in-orbit research studies. For the 10 European nations that designed, constructed, and financed Spacelab jointly through the European Space Agency and for the National Aeronautics and Space Administration, which designed, constructed, and financed the Spacelab ground facilities and manages the Spacelab flights, this is the culmination of history's largest and most comprehensive multinational space project. Provided in this document is information on: (1) the nature of Spacelab; (2) interior design, equipment, and facilities; (3) Spacelab crew; (4) materials science and space plasma physics experiments; (5) experiments in the life sciences, astronomy and solar physics, and atmospheric physics and earth observations; (6) activities involved in a typical day aboard Spacelab; and (7) Spacelab's birth, impact, and future. (Text material is supplemented by color photographs and diagrams.) (JN)