Web 2.0 and Social Software revolutionize the knowledge exchange within and between organizations. This is one of the claims consultants and software vendors in the field have made. But have the promises been kept and has evidence been achieved so far, in particular for knowledge management in globally distributed settings? As a starting point, our paper introduces the field of Global Social Knowledge Management (GSKM). We see this area as one of the main research area for future research in the Knowledge Management domain leading to changing practices in organizations. A variety of social software applications have already been seen promising and incorporated into the context of knowledge management (Avram 2006; Zheng and Zheng 2010; Levy 2009). Inter- and intra-organizational micro-blogs (Zhao & Rosson 2009), social networks (DiMicco et al, 2008) or organizational wikis (Levy 2009) are just some examples for potential applications. One main assumption is that social software could bridge the traditional gap between human- and technology orientation (Avram 2006; Fiedler & Welpe 2011). However, there is so far only anecdotal evidence how these applications work in complex, globally distributed organizational settings. We see some initial indications that the field is very promising but it is highly necessary to perform more coordinated research. Within this paper, we present the key issues for GSKM. One of the most important issue is the choice of tools according to goals and processes. To support an adequate choice, we provide a mapping between Social Software, key barriers and knowledge activities. The main research domains related to GSKM are Social Software and Global Knowledge Management. We present a brief review of state of the art research for these domains and focus in detail on Social Software supported knowledge activities. We elaborate on the key barriers for GSKM that affect the usage and adoption of Social Software in KM activities. As one of the first efforts of mapping Social Software to KM, we present a Social Software framework, mapping the major barriers to tools and KM activities. We see this mapping as a crucial step towards finding the right tools for organizations' purposes. With this framework, we emphasize the need to analyze the implications of the global (cultural) influences to the existing and emerging Social Software-supported knowledge activities and processes. The paper is a starting point for discourse on this promising field, outlining the research field of globally distributed Social Software-supported Knowledge Management and discussing current research efforts on the main components. By this paper we intend to contribute towards a research agenda for Global Social Knowledge Management. [ABSTRACT FROM AUTHOR]