A decade of accession negotiations with the EU has not brought Turkey significantly closer to EU membership. In part the reasons lie with Turkey. This article, however, explores the position of the EU and the ‘supply-side’ of enlargement. It reflects on developments in how the EU has engaged with Turkey on the question of membership, situating Turkey’s candidacy and the EU’s position within the broader comparative context of how the process and politics of EU enlargement have evolved over the last ten years. It focuses on a set of supply-side variables that are key to determining the progress that applicants can make towards membership: member state preferences, the activism of supranational institutional actors, the EU’s integration capacity, public opinion in the EU towards enlargement, and the narratives deployed in justification of enlargement. The article also considers the state of Turkey’s accession negotiations and how they have been and potentially will be affected, assuming they are meaningfully revived, by the evolving nature and substance of EU accession negotiations more generally and EU’s approach to conditionality.