This paper analyses the existing legal frameworks within which a possible Sustainable Energy Trade Agreement (SETA) could be negotiated to address energy-related trade governance and the resulting legal challenges and opportunities. It looks at a number of options under which a SETA could be given legal shape within and outside the World Trade Organisation (WTO) and assesses the pros and cons of the various approaches. It touches on a number of important considerations, such as the negotiating procedures, issues of accession, relationship to existing WTO rules and obligations, and dispute settlement. The paper also puts forward arguments as to why the WTO would provide the best forum to house such an agreement. The paper, produced by the International Centre for Trade and Sustainable Development (ICTSD), is part of a joint initiative on the promotion of sustainable energy, undertaken by the Global Green Growth Institute, the Peterson Institute for International Economics and ICTSD.