Cities are growing more quickly than ever. As centers of economic, political and social life, urban areas are responsible for the vast majority of the world's energy use and greenhouse gas (GHG) emissions; they are the main contributors to air, noise, water and land pollution; they generate large quantities of waste; they are voracious consumers of natural resources; and they are particularly vulnerable to natural disasters and climate change. Given the current rates of urbanization, the environmental impacts of cities are giving rise to urgent concerns.How can city managers develop and deploy innovative initiatives and programs that can mitigate the negative environmental effects of urbanization? Can cities be part of the solution to overcome the current environmental challenges? Due to the higher population density and more effi cient allocation of resources in cities, can urban areas even be environmental pluses?This volume is part of a book series called "IESE Cities in Motion: International urban best practices." Cities and the Environment focuses on the effects of urbanization on our planet, and it aims to be: - an insightful analysis of the main environmental challenges that city governments face, - a catalog of international urban best practices on environmental issues, - a tool to help city managers and policy makers around the world develop innovative ideas and groundbreaking strategies in their endeavor to create green, sustainable and resilient urban areas that can improve people's quality of life.