That academic division of labour which once (and briefly) split the social sciences into the discrete study of the state (political science), economy (economics) and society (sociology) has broken down. Of course, such a division was never watertight. It is absent from most classical political theory and from the founding texts of both classical political economy and the sociological tradition. At a more mundane level, students of social policy, for example, have long had to consider the ways in which state, economy and society interact. Increasingly, students of sociology are required to understand the basic laws of motion of the state, just as students of politics and economics are increasingly required to place political and economic institutions in their appropriate social context. With these old lines of intellectual demarcation breaking down, it is now widely recognized that, in most developed societies, the state has probably been the single most important social, economic and political force.