For two decades, the central challenge facing climate-change policy makers involved efforts to control emissions of carbon dioxide. While diplomats looked at many different global-warming pollutants, they designed rules that mostly focused on carbon dioxide. Unfortunately, those efforts have largely failed, which has created yet another difficult challenge for the global community: how to manage the severe impacts of a warming world. New diplomatic strategies are needed. Diplomats must work harder on pollutants other than carbon dioxide—such as soot—that will be easier to regulate and can help build credibility in the international diplomatic regime. New science shows that soot and short-lived climate pollutants actually cause almost half of current global warming—much more than thought just a few years ago. Fortuitously, these pollutants are also relatively easy to manage, and success on this front will help catalyze the political support needed for the much more difficult, yet essential, task of making deep cuts in carbon dioxide. At the same time, the authors write, new thinking will be needed on how to help societies adapt, such as building networks of experts and local officials who are on the front lines of adaptation.