The vision of REFLOW is to develop circular and regenerative cities through the re-localisation of production and the re-configuration of material flows at different scales. More specifically, it will use Fab Labs and makerspaces as catalysers of a systemic change in urban and peri-urban environments, which enable, visualize and regulate “four freedoms”: free movement of materials, people, (technological) knowledge and commons, in order to reduce materials consumption, maximize multifunctional use of (public) spaces and envisage regenerative practices. Concretely, REFLOW aims at providing realistic best practices aligning market and government needs in order to create favourable conditions for the public and private sector to adopt circular principles. In order to provide critical examples of ways in which cities can adopt a CE model and reach the 2030 Sustainable Development Goals, REFLOW will create new CE business models (Distributed Design Market model, On-Demand System, Corporate Hacking and Corporate Pyramid) within 6 pilot cities (Amsterdam, Berlin, Milan, Paris, Vejle and Cluj-Napoca) and assess their social, environmental and economic impact. The project will make use of blockchain technologies in order to incentivise the circular practices in local ecosystems and data visualisation tools to enable continuous monitoring and optimisation of “urban metabolic” processes and rapid interventions management. Networks of sensors, urban computing and geo-localisation will capture data ensuring accuracy, integrity and interoperability of relevant data infrastructures, while data visualisation and standard templates will be available for effective communication, public consultation, and exchange of experiences.