A virtual Community of Practice (CoP) is a network of individuals who share a domain of interest about which they communicate online. The practitioners share resources (for example experiences, problems and solutions, tools, methodologies). Such communication results in the improvement of the knowledge of each participant in the community and contributes to the development of the knowledge within the domain. A virtual learning community may involve the conduct of original research but it is more likely that its main purpose is to increase the knowledge of participants, via formal education or professional development. Virtual learning communities could have learning as their main goal or the elearning could be generated as a side effect. Virtual communities of practice (CoPs) and virtual learning communities are becoming widespread within higher education institutions (HEIs) thanks to technological developments which enable increased communication, interactivity among participants and incorporation of collaborative pedagogical models, specifically through information communications technologies (ICTs) They afford the potential for the combination of synchronous and asynchronous communication, access to -and from- geographically isolated communities and international information sharing. Clearly there are benefits to be derived from sharing and learning within and outwith HEIs. There is a sense of connectedness, of shared passion and a deepening of knowledge to be derived from ongoing interaction. Knowledge development can be continuous, cyclical and fluid. However, barriers exist in virtual CoPs and these are defined by the authors and illustrated with quotes from academic staff who have been involved in CoPs. Critical success factors (CSFs) for a virtual CoP are discussed. These include usability of technology; trust in, and acceptance of, ICTs in communication; a sense of belonging among members; paying attention to cross-national and cross-cultural dimensions of the CoP; shared understandings; a common sense of purpose; use of netiquette and user-friendly language and longevity. The authors recognise the enormous potential for the development of CoPs through e-mail discussion lists and discussion boards but have themselves experienced the difficulties inherent in initiating such a community. These are corroborated and illustrated with text from interviews with academic staff. Much of the literature on CoPs emanates from outside Europe, despite the fact that e-learning articles have a large diffusion around Europe. The authors suggest further exploration of this topic by identifying and studying CoPs and virtual learning communities across EU countries. Additional author: Fontainha, Elsa