Political scientists are increasingly interested in understanding policymaking in civilian, defense and space technologies. The answer to the question why this is, is found partly in the emergence of the policy field itself, and partly in the enormously expanded role that government stimulus of technological innovation is playing in the public and private sectors. A listing of some recent programs — breeder and fusion reactor R&D, the space shuttle, windmill farm demonstration programs, synthetic fuels programs, and dial-a-ride transportation systems — gives some indication of the scope of federal involvement, and points up some of the implications that this enlarged role has for the student of public policy. Why, for instance, has government elected to stimulate innovations in certain technologies and not others? Who are the key actors shaping the policymaking process in R&D? Are their gaps in federal efforts? Is the policy system responding effectively to needs for renewable energy sources, alternative home building materials, gasoline-efficient automobile engines, etc?