Corruption and Uneven Development: Why Anti‐Corruption Fails in the EU 's Most Vulnerable Regions

This article challenges the assumption that legal harmonization within the European Union ensures effective anti‐corruption governance. Despite EU‐compliant frameworks, institutional integrity remains highly uneven across subnational territories. We introduce the Regional Integrity Framework (RIF), a diagnostic approach that integrates citizen perceptions, procurement indicators, and enforcement activation measures to capture regional integrity performance. The analysis suggests that formal convergence can conceal functional divergence, as peripheral regions often exhibit weaker administrative capacity, limited oversight, and uneven institutional activation. A mixed‐methods application that combines panel analysis with an illustrative comparison of Sofia and Vidin, Bulgaria, demonstrates how the RIF can diagnose territorial integrity gaps within a shared legal framework. Conceptually, the study reframes anti‐corruption as a territorially embedded problem of institutional activation; methodologically, it offers a transferable framework for identifying enforcement asymmetries and governance disparities in multi‐level systems.