This chapter explains the community of practice (COP) concept from the perspective of three major Australian construction contractors. It also describes and provides an analysis of their COPs from the perspective of the individual, work group, and organisation. We provide maps of these COPs for each of the three contractors studied. The intention of using this approach is to offer readers insights into how these COPs can be developed and supported. The study we base this chapter upon focussed on groupware as an ICT initiative being rolled out using COPs as an integral part of the innovation diffusion strategy. Case study findings relating to these COPs reveal that they are not only supported by ICT, but also that ICT itself supports these COPs in a self-referential and synergistic way. The important contribution that this chapter makes to our understanding of the studied phenomenon was not only the ‘what’ or descriptive nature of these COPs, but also insights that help us understand the ‘how’ of the process, so that lessons learned may be absorbed and diffused more widely in the construction industry.