addresses technologies that cut across the responsibilities of the mission offices (e.g., spacecraft system and subsystem technologies, launch technologies) and exploratory technologies potentially applicable to missions of the more distant future. In both areas, NASA exercises field center capabilities in carrying out technology projects, either as in-house projects or through contracts with outside sources. The exploratory technology program of OSAT most nearly resembles the ARPA program in purpose— advancement of potentially high payoff technologies for future space missions. But the way it is conducted is quite different, relying, as it does, on an essentially permanent management staff in Headquarters and a large, also permanent, research establishment at the field centers.