What is the value of a circular innovation if you cannot prove the actual impact? If there is no economic value? If no one wants it, it is too complicated for use or it is simply not producible? The Leiden-Delft-Erasmus Centre for Sustainability aims to realize a Circular Economy, focusing on resource efficiency, by deriving questions from the market and creating true impact by answering these questions through science. The ultimate aim is to create an open innovation centre that works on multi-year roadmaps build with stakeholders from society: companies, governments and NGO’s. Through knowledge labs market demand will be translated into scientific questions. Students, start-ups and scientists will work on satisfying market demand with proven positive impact on a circular economy. By actively translation scientific results into practical applications that the market is actively waiting for, a true circular economy will get closer rapidly.