In an effort to replicate Communities of Practice online, organizations are investing in information technologies that create intra-organizational electronic networks, or "Electronic Networks of Practice". These networks are designed to enable the creation of electronic "bridging ties" between geographically dispersed organizational members to provide a communication space in which individuals working on similar problems may quickly ask each other for help on task-related problems. This chapter compares the dynamics of knowledge exchange between Electronic Networks of Practice and traditional Communities of Practice. In addition, this chapter examines why people participate and help others in the network, as well as whether participation has an impact on knowledge outcomes and individual performance. In order to investigate these issues, data were collected from a successful electronic network at one of Europe's largest consulting companies. The chapter concludes with a discussion of the results and implications for both managers and researchers interested in the dynamics of electronic knowledge exchange.