The concept of regionalism contains, first of all, a significant political dimension in which the effort to strengthen the political influence of regional units in the structure of the division of state power is expressed. The historical roots of the idea of regionalism are linked to the transition from the 18th to the 19th century and the resistance to the concept of the nation state that evolved on the European continent, first after the French Revolution. The idea of regionalism went through an evolutionary path of its development in the thinking and practice of certain institutions that brought documents in which this idea was further elaborated, polished and harmonized. Regional policy is part of the public policy of the European Union, and it is aimed at reducing the social and economic differences that exist between the countries and regions of the member states of the Union. It is a special type of economic policy aimed at increasing the competitiveness of the economy of those areas that lag behind the European average. This policy aims to enable less developed areas to catch up with more developed areas and become involved in economic costs as active entities. Regional development policy represents one of the pillars of the overall public policy of the European Union and is aimed at the redistribution of funds from member states of the Union in order to encourage economic growth and sustainable development of those areas that are lagging behind. The issue of regionalism in Croatia has repeatedly been the subject of discussion and controversy among the scientific and professional public. In Croatia, throughout its history, political regionalization has mostly dominated, either as its own product or as a product of foreign administrations. The current regionalization of Croatia mainly follows the needs of the administrative-political structure, and less economic criteria, although the Republic of Croatia should be centralized, relying on rich European models. The benefits of decentralization for Croatia would be multiple.