North American policy responses to global climate change are complex and sometimes contradictory and reach across multiple levels of government. For example, the U.S. federal government rejected the Kyoto Protocol and mandatory greenhouse gas (GHG) restrictions, but California developed some of the world's most comprehensive climate change law and regulation; Canada's federal government ratified the Kyoto Protocol, but Canadian GHG emissions increased even faster than those of the United States; and Mexico's state-owned oil company addressed climate change issues in the 1990s, in stark contrast to leading U.S. and Canadian energy firms. This book is the first to examine and compare political action for climate change across North America, at levels ranging from continental to municipal, in locations ranging from Mexico to Toronto to Portland, Maine. Changing Climates in North American Politics investigates new or emerging institutions, policies, and practices in North American climate governance; the roles played by public, private, and civil society actors; the diffusion of policy across different jurisdictions; and the effectiveness of multilevel North American climate change governance. It finds that although national climate policies vary widely, the complexities and divergences are even greater at the subnational level. Policy initiatives are developed separately in states, provinces, cities, large corporations, NAFTA bodies, universities, NGOs, and private firms, and this lack of coordination limits the effectiveness of multilevel climate change governance. In North America, unlike much of Europe, climate change governance has been largely bottom-up rather than top-down.