Communities of Practice (CoPs) are being increasingly employed in organizations and are probably the knowledge management tool today. They are a truly useful knowledge-sharing, transferring and retaining tool, surpassing other int- organizational networks such as project teams, operational teams, and purely informal networks. They also enjoy far greater success than pure IT tools employed to similar ends. The advantage is that they are based on like-minded people’s fa- to-face meetings, exchange of experience, discussion and development of best practices etc. on an intra-organizational level, although these activities are often informal and not supported or recognized. As ever, practice has shown that many intra-organizational CoPs simply do not work while others are truly successful. The thesis provides the readers with some surprising insights into the nature of CoPs and the specific contributing factors. Stefano Borzillo’s meticulous research started off by examining a large variety of CoPs by means of six identified success factors. The results of Stefano’s investigation revealed three types of CoPs, which he calls “innovating strategic”, “operational excellence”, and “social and productive space” CoPs and which may all three be present within a single organization. Another insight in this regard was that each of them is suited to fulfill different objectives and that there is no one type of CoP that is best for managing the development and transfer of practices. The latter is determined by the CoPs’ objectives, which are again determined by the organizational context. Stefano Borzillo also describes each of these CoP configurations’ success factors.