Over the last decade, the concept of circular economy (CE) has gained momentum among practitioners, politicians and scholars because of its promise of achieving sustainability goals. However, there is still a need to demonstrate and assess the positive environmental impacts of CE. With respect to the building sector, CE is still a relatively new topic. To date, research has tended to focus primarily on the macro scale (cities or eco-parks) and micro scale (manufactured products or construction materials). Nevertheless, the often-neglected built environment also is expected to play a crucial role due to its high contribution to various environmental burdens. Accordingly, this chapter aims to contribute to this growing area of research by reviewing four cases of ‘circular neighbourhood’ projects in Europe. First, a conceptual framework analysis is defined and applied to the cases. Second, CE initiatives and actions are identified and classified using interviews and document analysis. Third, the use of assessment tools within these CE projects is investigated. The results demonstrate a diverse representation of the CE paradigm and a growing role played by the assessment tools.