AMB is the public administration of the metropolitan area of Barcelona, a large urban conurbation with a population of over 3.2 million which generates half of the Catalonia’s GDP. The AMB powers are related to urban planning, mobility, environment, waste management, Integrated water cycle and economic development. This central position in the articulation of metropolitan metabolic flows is an opportunity to boost environmental improvement strategies. Thus, the AMB will present its main projects to promote the circular economy among its productive activities, with special attention to waste flows, raw materials, energy and water.