Social scientists have long assumed that actions by states to reduce their greenhouse gas emissions are not in their self-interest because the domestic costs outweigh the domestic benefits, leading to an assumption that they can “free-ride” on the emissions reductions achieved by others states. Climate change action, on this logic, is a global “tragedy of the commons” and “prisoner’s dilemma”. While this view is increasingly being challenged by theory and evidence suggesting that much mitigation action would in fact be in states’ self-interest, this emerging literature is fragmented and has not succeeded in overturning the traditional assumptions, at least not in key social science reference works such as the reports of Working Group III of the Intergovernmental Panel on Climate Change.This paper, produced by the Centre for Climate Change Economics and Policy (CCCEP), seeks to rectify this problem by developing a unified conceptual framework for advancing and evaluating claims about the extent of mitigation action that could be done in states’ self-interest, defined here in terms of economic efficiency. Following an introduction, the paper introduces and defines key concepts before outlining the conceptual framework used, and the potential for national net benefits to arise from the mitigation action classified within this framework. This framework includes the integration of two sub-categories of actions: directly and contingently nationally-net-beneficial mitigation actions, and the associated concept of “contingency risk”.The paper then concludes that there is a strong prima facie case that the majority of the emissions reductions needed to decarbonise the global economy can be achieved in ways that are nationally net-beneficial to countries, even leaving aside the climate benefits. Accordingly, the default assumption in social science scholarship should be that actions to reduce emissions are nationally net-beneficial. In proposing an alternative view for why progress appears slow, the paper proposes that barriers to mitigation action lie, primarily, not in the macro-incentive structures of states, but rather within the domestic sphere, at the intersection of domestic interests, institutions and ideas formed in the fossil fuel age.[Adapted from source]