The research project REFLOW sets out to offer a new approach to circular economy (CE) in urban areas. REFLOW will provide best practices aligning market and government needs in order to create favourable conditions for the public and private sector to adopt CE practices. Active citizen involvement and systemic change are needed to re-think the current approach. Concretely, REFLOW will create new CE business models within 6 pilot cities: Amsterdam, Berlin, Cluj-Napoca, Milan, Paris and Vejle and assess their social, environmental and economic impact. In each of the pilots, citizens will be involved in developing and testing circular products, software, and business models for their own city. REFLOW’s ambition is to offer tools and guidelines that other cities can adopt.