The progress of European integration is perhaps nowhere more visible than in the EU's border regions. In places where thousands of people cross national frontiers every day, the European project becomes lived reality. Yet navigating between the differing legal systems of the Member States still hampers seamless cross-border cooperation. With the regulation establishing the "European Grouping of Territorial Cooperation" (EGTC), a binding legal framework for cooperation between regions and municipalities of different Member States was created for the first time. But can the EGTC, in its theoretical conception and practical implementation, sustainably strengthen the cohesion of the Union? Drawing on an empirical analysis of all EGTCs active across Europe, Cathrin Cordes demonstrates that the grouping fosters European integration at least on a formal level: it connects decision-makers across administrative tiers and national borders, thereby creating a functional space for cooperation. However, due to limited civil society participation, the EGTC often lacks democratic legitimacy. In addition, it cannot overcome the barrier of divergent legal rules that meet at national borders. For the future development of European integration, it therefore seems essential to view the EU not only from the vantage point of national capitals, but also from its border regions - places where innovative forms of cooperation can be tested.