First published in 1975, this collection of essays embodies a conception of sociological thought as a critical analysis of social theories and doctrines, of social institutions and political regimes, of recent social movements. They deal, in particular, with some conservative versions of sociology and with attempts to develop more radical theories; they extend the author's previous writings on classes, elites and politics; and they analyse some of the problems of socialism in the late twentieth century. There is a close unity of theme througout the book in its critical attempt to formulate new intellectual bases for future radical and egalitarian politics. It is written with that quiet wisdom and impressive command of sources which readers have come to associate with Professor Bottomore's work.