This is a presentation I have given for a group of students, which are joining for a study trip to Copenhagen and Malmo. The study trip is focussing on innovative ideas and cases with show cases in the two cities around the three core topics of this excursion: 1. Urban Metabolism 2. Urban Food 3. Urban Climate. My presentation was a contribution to the topic "Urban Metabolism" and includes some of the ideas of our research group. The trip has been organized by RUW, a Wageningen foundation. RUW organizes activities about "green issues" These activities facilitate the exchange of knowledge and views between students, scientists, policymakers, industry and other relevant actors. By its activities, RUW contributes to a dynamic platform for everybody who wants to discuss, share and gain knowledge about green issues such as group discussions, lectures, debates and excursions.