In the history of sociological theory, Talcott Parsons holds a very special place. His The Structure of Social Action (1937), was a pioneer work that has influenced many social scientists. The present work, The Social System, presents a major scientific and intellectual advance towards the theory of action first outlined in his earlier work.‘Social science is concerned with human beings interacting with one another in terms of mutually accepted standards of conduct. Their interaction takes place in an environment of what one might call “brute fact”, which comprises, among other things, climate, material resources, the population structure and the physical possibilities of communication. To study this vast complex of material some scheme of concepts is required, by means of which we can pick out what is significant, and so pave the way for discovering “what goes with what”. It is such a scheme that Professor Talcott Parsons has worked out, in his latest book. It is an important book.’The Listener