How do the flows of goods, people, waste, biota, energy, food, freshwater, sand and air function in Rotterdam? What influence do these flows have on the quality of life in the city, and how do they relate to spatial developments? Can an insight into the metabolism of Rotterdam help us develop into a sustainable region? And what opportunities are there for a circular economy? This publication details the results of the IABR–PROJECT ATELIER ROTTERDAM. The analyses, the strategies developed and the specific design proposals detailed, provide answers to the questions posed above. The results obtained offer not only the municipality but also other parties in the city specific pointers for continuing to work on the metabolism of Rotterdam.