The sustainable city debate is gaining ground in recent years, featuring as a prominent issue in several policy documents of the European Commission, and enjoying support by the main organisations and institutions at international level. At the same time, improving local governance standards by involving citizens in local decision-making is a recurring issue in the debate on local democracy and enhancement of community cohesion. This paper presents an analysis of the European experience and best practice relating sustainable development to the day-to-day practice of spatial planning. The overall purpose is creating a proposal of indicators for measuring the sustainability of planning actions in urban environments.