Beyond institutions: Functional integration, cross-border flows, and the limits of European border integration

This article examines the functional dimension of cross-border integration in European border regions, focusing on everyday cross-border flows as key mechanisms shaping territorial integration beyond formal institutional arrangements. It addresses the growing mismatch between dense socio-economic interactions across borders and the often-limited capacity of institutionalized cross-border cooperation to stabilize or govern these processes. Drawing on relational and flow-based perspectives in border studies and regional geography, the article conceptualises functional integration as a practice-based process rooted in regular mobility, service use, and economic exchange. The analysis is based on a critical synthesis of existing theoretical and policy-oriented literature. It introduces cross-border functional areas as an analytical construct capturing the spatial imprint of stabilized cross-border interactions. Rather than treating these areas as formal territorial units or normative policy objectives, the article highlights their dynamic, sectorally differentiated, and politically contingent character. Particular attention is paid to structural asymmetries between national systems, the selective permeability of borders, and the vulnerability of functional integration in highly regulated policy domains. The main contribution of the article lies in clarifying the analytical value of functionality for understanding both the potential and the limits of cross-border integration. By decoupling functional integration from institutional density, the article provides a conceptual framework for interpreting uneven integration patterns and for future empirical research on cross-border governance and resilience in European borderlands.