This thoughtful and penetrating book, addressed to political scientists, sociologists, historians, and anthropologists, interprets nationalism in terms of its social roots, which it locates in industrial social organization. Professor Gellner asserts here that a society's affluence and economic growth depend on innovation, occupational mobility, the effectiveness of the mass media, universal literacy, and an all-embracing educational system based on a shared, standard idiom. These factors, taken together, govern the relationship between culture and the state. Political units that do not conform to the principle, "one state, one culture" feel the strain in the form of nationalistic activity.