What is industrial policy? postwar Japanese industrial policy - an historical overview. Part 1 Industrial promotion and trade: industrial policy and changing industrial structure; theories of infant industry protection - an overview; industrial set-up costs and Marshallian externalities; scale economies and information; choice of industrial structure and economic welfare. Part 2 Oligopolistic control of an international market: strategic behaviour and Nash equilibrium; international redistribution of monopoly rents; strategic entry deterring behaviour and entry assistant policy; strategic intervention in international competition - significance and limitations. Part 3 Welfare implications of strategic competition in oligopolistic industries: the concept of competition - an evaluation; economic implications of entry restriction policies; investment competition and economic welfare - a reconsideration of the concept of "excessive competition". Part 4 Research and development investment: characteristics of technical knowledge and incentives for research and development; traditional theory of research and development and under-investment; research and development competition and excess investment introduction ; market structure and research and development - innovation, improvement, and imitation; research and development and industrial policy - with special reference to research and development associations. Part 5 Further problems in formulation of future industrial policy: problems related to industrial adjustment policies; internationalization of the economy and industrial policies.