Abstract
Domestic regional policies are increasingly expected to tackle significant spatial disparities, promote territorial justice, and ensure equal opportunities, thereby supporting various aspects of sustainability. This article focuses on the case of Bulgaria, serving a dual purpose: it outlines the emergence and evolution of contemporary regional policy in the country and measures the extent and dynamics of socio-economic inequalities at different territorial levels. The conceptualization of a comprehensive regional policy framework following the socialist era was largely driven by top-down Europeanization impulses, which catalysed political debates on the transformed roles of the regions and the necessity for effective decentralisation. However, despite years of domestic regional policy implementation, socio-economic inequalities in Bulgaria remain substantial, with certain peripheral regions notably trailing behind. The comprehensive assessments conducted in this study include primarily descriptive statistics, regression and correlation analyses, time series analyses, and classification/categorization of territorial units. They indicate significant spatial heterogeneity and the prevalence of pronounced ‘centre-periphery’ patterns, which pose a serious threat to the long-term sustainable development of the country.