This article examines the prospective role of the G20 (Group of Twenty) in contributing to current efforts to address climate change. This article contends that the G20 has the potential to be a site of policy coordination of economically significant states and transnational policy actors which could support the implementation of the Paris Agreement reached at the 21st conference of the parties (COP21) of the United Nations Framework Convention on Climate Change (UNFCCC) in 2015. While this article demonstrates that the G20 and its predecessors have considered the topic of climate change without great success, it articulates the ways that recent developments within the operation of the G20 offers new prospects for addressing this crucial policy issue. These prospects rest primarily upon seeing the G20 as a form of global summitry which is not only an international forum but also a transnational framework of policy makers which offer the possibility that G20 deliberations can be more open to a wider variety of perspectives and more effectively engage with transnational efforts to address climate change.