Communities of practice have become prevalent in today’s business and educational environments. Loosely defined, communities of practice (CoPs) are informal groups within or across organizations. These groups are viewed to have a common set of information needs or problems. Davies, Duke, and Sure (2003) suggest that while not a typical organizational unit, these informal, work-oriented networks share a common agenda, interests, or issues. Millen and Fontaine (2003) assert that these communities are defined by a common disciplinary background, similar work activities and tools, and have shared stories, contexts, and values. Burk (2000) says CoPs are expansions of one-on-one knowledge sharing. This article discusses first the background to such issues as team formation, member participation, and sustained membership; it then considers future trends in knowledge capture and sharing, and the support such communities require.