This book charts the course and causes of UN, G7 and G20 governance of climate change through the crucial period of 2015–2021. It provides a careful, comprehensive and reliable description of the individual and interactive contributions of the G7, G20 and UN summits and analyses their results. The authors explain these contributions and results by considering the impacts of causal candidates, such as a changing physical ecosystem and international political system and the actions of individual leaders of the world’s most systemically significant countries. They apply and improve an established, compact causal model, grounded in international relations theory, to guide these tasks. By developing, prescribing and implementing immediate, realistic actionable policy solutions to cope with the urgent, existential challenge of controlling climate change, this volume will appeal to scholars of international relations, global governance and global environmental governance.