Michael Jäger is group leader for sustainable construction at the Fraunhofer IBP. As an economist and sustainability researcher, he is particularly interested in the question of how to align economic growth with sustainable development. Within platforms2share, he is developing an impact assessment model for different organizational and business models of the sharing economy by taking into account rebound effects. More generally, one of his main concerns is to assess solutions for the future living in buildings, districts and cities with regard to their sustainability. Thanks to his work for platforms2share, he can now expand his focus by including the important aspect of user and usage interactions in order to be able to assess future living spaces holistically.