PATHFNDR (PATHways to an Efficient Future Energy System through Flexibility aND SectoR Coupling) is a research project sponsored by the Swiss Federal Office of Energy’s “SWEET” programme and hosted by ETH Zurich. The project consortium is represented by seven research partners - ETH Zurich, Empa, PSI, ZHAW, HSLU, UNIGE, EPFL - and 25 cooperation partners. The project aims to develop and analyze transition pathways for renewable energy integration in Switzerland. The project will deliver feasible pathways, provide planning and operation tools, develop pilot and demonstration projects, identify new business opportunities and innovation strategies, and analyse potential policies.