The Wuppertal Institute for Climate, Environment and Energy (WI) is a research institute and think tank for sustainable development. It undertakes research and develops models, strategies and instruments for transitions to sustainable development at the local, national and international level. Among others, WI has a long record of leading and participating in European projects in the energy field, for example, social, economic, and technical analysis of policies and measures fostering energy efficiency and renewable energies. The WI coordinated the COMBI project, which aimed at quantifying the multiple non-energy benefits of energy efficiency in Europe and the development of an online-tool. In MICAT, WI is in charge of WP2 (Conceptual Framework) and has a major role in WP3 (Impact Assessment) as well as WP4 (Tool Development).