For decades, public and scholarly debates on large, post-war housing estates in western Europe have been concerned with social decline. After 1989/1990, the point in time of fundamental societal change in eastern Europe, this concern was transferred to estates in post-socialist cities. However, empirical evidence for a general negative trend has not emerged. Recent publications confirm the persistence of social mix and highlight the differentiated trajectories of estates. This paper aims to contribute to an approach of how to conceptually make sense of these differentiated trajectories. Using data from a unique longitudinal survey in East Germany, starting in 1979, we investigate the state of social mix, drivers of social change and the inner differentiation in the housing estate Leipzig-Grünau. We found no proof for a dramatic social decline, rather there is evidence for a slow and multi-faceted change in the social and demographic structure of the residents contributing to a gradual social fragmentation of the estate. This is a result of path dependencies, strategic planning effects and ownership structures. We discuss these drivers of large housing estate trajectories and their related impacts by adapting a framework of multiple, overlapping institutional, social and urban post-socialist transformations. We suggest embedding the framework in a wider and a local context in which transformations need to be seen. In conclusion, we argue for a theoretical debate that makes sense of contextual differences within such transformations.