Differentiated by Design? Cross‐Border Cooperation in Europe as Differentiated Integration From Below

Abstract Differentiated integration has become a central concept in contemporary theorizing about European integration, reflecting the increasingly multi‐speed, multi‐tier and multi‐menu nature of integration within the European Union (EU). This research note extends the conceptual lens of differentiated integration to the level of cross‐border regions. We argue that variation in speed, depth and territorial scope of integration across cross‐border regions arises both from differing levels of regional engagement and from differing support and initiatives at the member state level. The result is a patchwork pattern of cross‐border integration across Europe. We further explore the causes of cross‐border regional differentiated integration as well as its consequences and its potential to shape European integration as a whole. Specifically, we identify institutional and societal channels through which cross‐border policy ideas may diffuse vertically and horizontally and potentially influence public attitudes in border regions towards EU and cross‐border integration.