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...