A range of efforts to meet the climate challenge in cities, identifying energy, buildings, waste, transportation, and deforestation as areas that offer the potential for large reductions in greenhouse gas emissions. 

This section also broadens the lens to consider a number of other issues that are important for urban sustainability, including social justice, biodiversity, and the  “remunicipalization” of select urban functions such as power and water.

Although actual gains in these sectors are not yet in the range that would make a city fully sustainable, the section offers numerous policy ideas that could help us move, live, and work much more cleanly. Many of these ideas already are being implemented in cities worldwide, and more cities can be encouraged to replicate the most ambitious and successful of these initiatives.