This is a collaboration between Marlous Agterberg, Marleen Huysman, Bart van den Hooff and others, and focuses on the use of social software (social media) within organizations. We focus on the affordances and constraints of these tools as they are shaped in the interaction between users and tools, and how these affordances and constraints affect processes of knowledge sharing and collaboration within organizations. We are currently starting up two projects in large multinational organizations which have implemented, or are in the process of implementing, such tools. We use a combination of content analysis, surveys, interviews and observations to analyze the use and effects of these tools. We would very much appreciate collaboration with other organizations with practical interest in and experience with these tools.