Building on the book’s assessment of the incentives of cities to protect the environment, the chapter outlines an agenda for cities to meet the challenges presented by climate change. The chapter starts by charting an agenda for cities to adapt to the impacts of planetary climate change, because cities have the greatest incentives and levers to address this aspect of the climate challenge. Then the chapter identifies plausible contributions that cities can make to societal decarbonization. The federal government has been, at best, an inconsistent partner in decarbonizing the economy. Climate regulation in major cities provides a means of ensuring that the societal decarbonization project continues to advance, regardless of who is in power federally. The chapter emphasizes the need for higher levels of government to better support municipal efforts to tackle climate change and suggests ways for lawmakers at higher levels of government, in particular the federal level, to do so if they are interested in environmental protection.