Before beginning the study of the social system I have chosen to call ‘state socialism’, it is necessary to define the term and to describe the societies to which it is held to apply. A society may be defined as a behavioural system having three components : a distinct set of central or dominant value and beliefs, a number of social institutions, and patterns of interactions between individuals and institutions. What, then, are the distinguishing features of state socialism? The dominant values are those of Marxism-Leninism, andthepeculiar institutions of the system stem from the state-owned means of production which determine man’s relationship to property. The values laid down in the charter of the society are those of socialism : that is, a system of beliefs focused on the ultimate perfectibility of man, on the determining influence of class forces operating through the laws of historical and dialectical materialism. In state-socialist societies, the dominant institution is the Communist Party, which is considered to lead the working class and provides an authoritative interpretation of the laws of historical development, which in turn legitimate the Party’s own political power. The appellation state focuses on the central role played by government and Party institutions in the process of these societies : not only do ownership and control of the means of production legally reside with the state, but it has the authority to mobilise the population to achieve the goals defined in the ‘official charter’. In the patterns of interactions between institutions, the state (government and ruling party) plays a dominant role. Let us now turn from analytical concepts to consider some historical generalisations.