Abstract. The rise of online social networks (OSNs) has traditionally been accompanied by privacy concerns. These typically stem from facts: First, OSN service providers' access to large databases with millions of user profiles and their exploitation. Second, the user's inability to create and manage different identity facets and enforce access to the self as in the real world. In this paper, we argue in favor of a new paradigm, decoupling the management of social identities in OSNs from other social network services and providing access controls that take social contexts into consideration. For this purpose, we first propose Priamos, an architecture for privacy-preserving autonomous management of social identities and subsequently present one of its core components to realize contextaware access control. We have implemented a prototype to evaluate the feasibility of the proposed approach.