Sustainable development has become a globally accepted policy objective. It is, however, increasingly recognised that the implementation of sustainability strategies has to take place at a decentralised level. This has also provoked the idea of urban sustainability. This paper aims to offer a refreshing contribution by making a plea for market solutions for urban sustainability problems. Particular attention is given to the potential contribution of tradeable permits for various polluting activities (air pollution, water pollution, congestion energy consumption, etc.). The idea is that such market strategies may favour efficiency, equity and environmental quality in the city. An overview of various possibilities is given, followed by policy guidelines and conclusions.