The collection of articles in this special issue provides a comprehensive analysis of European Union decision-making during the Eurozone crisis. We investigate national preference formation and interstate bargaining related to major reforms of the Economic and Monetary Union. The analyses rely on the new ‘EMU Positions’ dataset. This dataset includes information about the preferences and saliences of all 28 EU member states and key EU institutions, regarding 47 contested issues negotiated between 2010 and 2015. In this introductory article, we first articulate the motivation behind this special issue and outline its collective contribution. We then briefly summarise each article within this collection; the articles analyse agenda setting, preference formation, coalition building, bargaining dynamics, and bargaining success. Finally, we present and discuss the ‘EMU Positions’ dataset.