More than two decades of international negotiations have failed to stem emissions of greenhouse gases that are causing global warming and climate change. This book identifies a way to escape this ongoing tragedy of the atmospheric commons. It takes a fresh approach to the ethics and practice of international environmental justice and proposes fundamental adjustments to the climate change regime, in the process drawing support from cosmopolitan ethics and global conceptions of justice. The author argues for 'cosmopolitan diplomacy', which sees people, rather than states alone, as the causes of climate change and the bearers of related rights, duties and obligations.