The author advocates the view that social and political history should join forces to research State Socialist systems. His central point is that focusing solely on the relationship between rulers and ruled, typical of the standard concept of totalitarianism, obscures the reasons for both stability and change in these systems. In order to understand the phenomena, one must comprehend which social groups viewed their interests as protected by the Socialist order. The fact that Socialist systems could not exist without being considered legitimate by relevant parts of society is demonstrated, among other things, by attempts at reform that were inspired both ‘from above’ and by parts of the critical, but loyal intelligentsia. Last but not least, the continuity of élites after 1989 demonstrates the importance of taking into account a social reality which may very well deviate from the relationships of power being proclaimed: in the late period of State Socialism, informal relationships of power and property had long since been established, and could easily be carried over into the period after the changes.