Governing the Climate-Energy Nexus fariborz zelli, karin ba ¨ckstrand, naghmeh nasiritousi, jakob skovgaard, and oscar widerbergEnergy and climate change are fundamentally connected. In today's world energy production and use account for two-thirds of global greenhouse gas emissions (IEA 2018). To curb the climate crisis and to meet the goals set out in the Paris Agreement, we need to provide reliable and affordable energy to some 10 billion people. This much needed transition to low-or zero-carbon societies would have profound consequences for the world's energy systems (Lesage and Van de Graaf 2016). Many steps have already been taken to bring this transition on its way, and they include an ever-increasing number of governance initiatives across borders. The success of this transitionand therewith the future quality of life on our planetdepends on how effectively and legitimately these various governance efforts achieve their goals, and this without undermining each other too much. In short, coordinated policy responses to limit climate change and decarbonize energy systems worldwide need to go hand in hand.Against the backdrop of this urgent link between global climate change governance and global energy governance, this volume puts the 'climate-energy nexus' at the forefront. Both governance structures making up this nexus are highly complex (Sovacool 2013;Goldthau et al. 2018). Efforts to tackle climate change have increased significantly over the past twenty and more years, and they have expanded far beyond the multilateral response under the United Nations Framework Convention on Climate Change (UNFCCC) (Vogler 2018). These efforts vary from minilateral, local, and transnational initiatives to private regulation, technology agreements, and market-based mechanisms (Hoffman 2011; Hjerpe and Nasiritousi 2015). Likewise, governance efforts to address energy demands on the international level are fragmented, and even lack a core multilateral institution similar to the role the UNFCCC plays within the institutional complex on climate change (