The recent Paris Agreement to limit greenhouse gas emissions, adopted by 195 nations at the 2015 United Nations Climate Change Conference, signaled unprecedented commitment by world leaders to address the human social aspects of climate change. Indeed, climate change increasingly is recognized by scientists and policymakers as a social issue requiring social solutions. However, whereas psychological research on intrapersonal and some group-level processes (e.g., political polarization of climate beliefs) has flourished, research into other social processes—such as an understanding of how nonpartisan social identities, cultural ideologies, and group hierarchies shape public engagement on climate change—has received substantially less attention. In this article, we take stock of current psychological approaches to the study of climate change to explore what is “social” about climate change from the perspective of psychology. Drawing from current interdisciplinary perspectives and emerging empirical findings within psychology, we identify four distinct features of climate change and three sets of psychological processes evoked by these features that are fundamentally social and shape both individual and group responses to climate change. Finally, we consider how a more nuanced understanding of the social underpinnings of climate change can stimulate new questions and advance theory within psychology.