IEEE Internet Computing: Special Issue on Security and Privacy in Social Networks May/June 2011 (Abstract submission due: August 15, 2010, Paper submission due: September 1, 2010) Guest Editors: Gail-Joon Ahn (Arizona State University), Mohamed Shehab (UNC Charlotte) and Anna Squicciarini (Penn State University) Social networks where people exchange personal and public information have enabled users to connect with their friends, coworkers, colleagues, family and even with strangers. Several social networking sites have developed to facilitate such social interactions and sharing activities on the Internet over the past several years. The popularity of social networking sites on the Internet introduces the use of mediatedÐcommunication into the relationship development process. Also, online social networks have recently emerged as a promising area of research with a vast reach and application space. Users post information on their profiles to share and interact with their other friends in the social network. Social networks are not limited to simple entertaining applications; instead several critical businesses have adopted social networks to attract new customer spaces and to provide new services. The current trends of social networks are indirectly requiring users to become system and policy administrators for protecting their content in this social setting. This is further complicated by the rapid growth rate of social networks and by the continuous adoption of new services on social networks. Furthermore, the use of personal information in social networks raises entirely new privacy concerns and requires new insights on security problems. Several studies and recent news have highlighted the increasing risk of misuse of personal data processed by online social networking applications and the lack of awareness among the user population. The security needs of social networks are still not well understood and are not fully defined. Nevertheless it is clear these will be quite different from classic security requirements. It is important to bring a depth of security experience from multiple security domains and technologies to this field as well as depth and breadth of knowledge about social networks. The aim of this special issue is to encompass research advances in all areas of security and privacy in social networks. We welcome contributions relating to novel technologies and methodologies for securely building and managing social networks and relevant secure applications as well as to cross-cutting issues. Topics of interest: include but are not limited to - Access control and identity management - Delegation and secure collaboration - Information flow, diffusion and auditing - Malware analysis in social networks - Privacy challenges and mechanism - Risk assessment and management - Secure social-network application development and methodologies - Secure object tagging, bookmarking and annotations - Trust and reputation management - Usability driven security mechanisms For more information, please see http://www.public.asu.edu/~gahn1/icsn2011.htm