Recent advances in ICT have led to the emergence of online social structures where the primary purpose is knowledge exchange. Using computer-mediated communication technologies, such as newsgroups, listservs, and bulletin boards, an unlimited number of geographically dispersed individuals with diverse organizational, national, and demographic backgrounds share knowledge through helping each other solve problems, debating issues around shared interests, and telling stories of personal experiences (Sproull & Faraj, 1995; Wasko & Faraj, 2000). Individuals benefit from participation in this online knowledge exchange since they gain access to help and expertise that are often not available locally. While knowledge exchange in traditional face-to-face communities of practice within organizations has received considerable attention, we know much less about the dynamics underlying electronic networks and have yet to reach a consensus defining the phenomenon of interest. For example, online social structures focused on knowledge exchange are commonly referred to by numerous names: virtual or electronic communities, communities of interest, and online communities. Additionally, both practitioners and researchers tend to take a unitary view of both communities of practice and electronic networks, thus masking possible heterogeneity along a number of important dimensions. Yet without clear definitions of electronic networks, it is difficult to apply overarching theories that are both appropriate and generalizable, to compare across studies, and to build a coherent stream of research. Thus, this article’s purpose is twofold: (1) to define and describe the specific characteristics of one form of online social structure, an electronic network of practice and (2) to compare electronic networks of practice with communities of practice in order to highlight the roles of each for supporting learning and knowledge exchange focused on a shared practice.