The chapters in this book provide a broad and fascinating survey of the state of debate on the relationship between climate change and human migration. This book could not have been timelier. As a joint statement by the major global change research programmes put it, “[t]he nature of changes now occurring simultaneously in the Earth System, their magnitudes and rates of change are unprecedented.” 1 While the 2015 Paris Agreement under the 1992 UN Framework Convention on Climate Change seeks to limit global warming to 2 degrees Celsius above pre-industrial levels, most current trends, as well as the aggregation of public policies, do not give much confidence that this goal will be reached. 2 Some studies suggest, for instance, that reaching the 2-degree target requires an 80 percent reduction of emissions in industrialized countries by 2050, 3 which seems, at present, to be highly demanding given current policies. Many doubt, moreover, whether reaching the “2-degree target” would even be sufficient to protect the most vulnerable places and communities from the impacts of climate change. What we need is a complete decarbonization of our patterns of consumption and production with the aim of reaching “negative emissions” (net uptake of carbon dioxide from the atmosphere) over the course of this century. Whether this will be possible, however, remains an open question. In short, while new mitigation initiatives are mushrooming in many places, it is far from certain that global warming can be limited to what is seen as safe levels.