Leen holds a PhD in energy in the built environment having done research on different aspects on that topic at KU Leuven, Strathclyde University, TU Eindhoven, Technical University of Texas in Austin and Vrije Universiteit Brussel. After several years in academics, she set up her own company Th!nk E. Th!nkE is an interdisciplinary team working on implementation, research & innovation and policy preparation work at national and European level. With Th!nk E, we also participate in technical assistance projects such as in the Clean Energy for EU Islands project, as well as provide technical, regulatory and legal expertise for Smart Cities in the Smart Cities Marketplace. Th!nk E has been acting as advisor in several building projects for different cities in Belgium and the Netherlands. Leen was member of the Advisory Group on Energy of the European Commission for 3 years and is today member of the Board of Flux50.