Cities are key in climate mitigation and adaptation, and they have developed into sites of innovative urban climate governance that can spur on climate action. Building on this development, a rich scholarship (within earth system governance and beyond) is now available that seeks to understand the development and performance of urban climate governance around the world. This article systematically reviews a decade of urban climate governance scholarship (building on 260 publications from 2009 to 2018). It is informed in this by four research challenges that were identified by leading scholars of urban climate governance a decade ago. The article seeks to understand how much progress has been made in the literature during this decade, and to identify the key research challenges for the critical decade that lies ahead of us.