SMARTEES is a transdisciplinary research project which aims to support the energy transition and improve policy design by developing alternative and robust policy pathways that foster citizen inclusion and take local peculiarities into account. To reach these objectives, SMARTEES examines five types of energy- and mobility-related local social innovation in ten front-runner cities and islands across Europe. The results stemming from this analysis will then feed into the development of a policy sandbox tool. Using a comprehensive modelling approach, this tool will help forecast the effects of policy measures and social innovation in similar local contexts, thereby supporting the improvement of policy design and decision-making. Through these means, the project will contribute to achieving a resilient, low-carbon and climate-friendly Energy Union that puts citizens at its core.