The significant change in our social lives and communication habits caused by the rise of Social Network Sites (SNSs) has not only brought along benefits but is also accompanied by privacy threats. In this paper we present our research efforts on SNS privacy and social identity management. First, we outline the results of an empirical study showing significant discrepancies between Facebook users’ actual privacy settings and their perception as well as their preferences. Based on this evident need for improving privacy, we present a novel conceptualization of privacy that serves as the basis for tackling the challenges. Finally, the paper provides an overview of solutions we developed as part of our research efforts on privacy in SNSs.