International cooperation to address the threat of climate change has become more institutionally diverse over the past decade, reflecting multiple scales of governance and the growing inclusion of climate change issues in other policy arenas. Cooperation under the United Nations Framework Convention on Climate Change has continued to evolve from the 1997 Kyoto Protocol to the 2015 Paris Agreement, while other governmental and private sector international fora for cooperation have arisen. As the level of activity in international cooperation on climate change mitigation has increased, so too has the related scholarly literature. In this review, we synthesize the literature on international climate change cooperation and identify key policy implications, as well as those findings most relevant for the research community. Our scope includes critical evaluation of the organization and implementation of agreements and instruments, retrospective analysis of cooperative efforts, and explanations of successes and failures.

The U.S. Clean Air Act, passed in 1970 with strong bipartisan support, was the first environmental law to give the Federal government a serious regulatory role, established the architecture of the U.S. air pollution control system, and became a model for subsequent environmental laws in the United States and globally. We outline the Act’s key provisions, as well as the main changes Congress has made to it over time. We assess the evolution of air pollution control policy under the Clean Air Act, with particular attention to the types of policy instruments used. We provide a generic assessment of the major types of policy instruments, and we trace and assess the historical evolution of EPA’s policy instrument use, with particular focus on the increased use of market-based policy instruments, beginning in the 1970s and culminating in the 1990s. Over the past fifty years, air pollution regulation has gradually become much more complex, and over the past twenty years, policy debates have become increasingly partisan and polarized, to the point that it has become impossible to amend the Act or pass other legislation to address the new threat of climate change.