The report introduces the concept of urban metabolism, the circular model and the role of compactness in urban resource efficiency. Cities require natural resources and energy to sustain the activities and daily life of the urban population. Nevertheless, there are opportunities to minimise the use of resources needed to sustain urban life and to reduce waste and emissions. As the urban form shapes the way people live, work and move, compact cities offer great potential to reduce the dependence on natural resources and energy. Urban planning, based on a vision of the future and developed with local stakeholders and crossing administrative borders, is a key factor in increasing the density of urban areas.