In cities, a circular economy model implies a systemic shift. Services, such as water, waste or energy, are provided making efficient use of natural resources as primary materials and optimizing their reuse. Economic activities are planned and carried out in a way to close, slow and narrow loops across value chains. Infrastructure is designed and built to avoid linear lock-in, for example by district heating and smart grid. Circularity in cities can be achieved by adopting policies in key sectors that advance solutions to climate change, such as food systems, buildings and cooling, and transport.