The aim of the research is to analyse the design and implementation of the European cohesion policy by applying multilevel joint actions of the European Union (hereinafter referred to as the EU), its institutions, its Member States, and their structures with an aim of achieving the European objective of equalising regional disparities within the territory of the EU. In particular, the following principles are considered: vertical division of competences, subsidiarity, proportionality of partnership, solidarity and co-financing. The basic hypothesis is that cohesion policy confirms that there is no development of the EU as a whole without the development of its constituents (Member States and regions). Research is focused on the EU as a political interstate community that has been seeking to standardize regional inequalities ever since its creation. In the EU, institutions and policies are mostly allopoietic, and cohesion policy should be the basis for transforming them into autopoietic forms. The purpose is to, on scientific grounds; consider shaping economic, social and territorial cohesion as the European acquis, shared competence between the EU and the Member States and its importance for services of general economic interest. In the implementation sense, the comparative method analyses the implementation of cohesion policy in EU Member States (Italy as a regional state, Slovenia as a unitary state and Germany as a federal state). A special chapter analyses the implementation of cohesion policy in the Republic of Croatia as a centralised unitary state. The final chapter focuses on analysing the impact of cohesion policy on the achievement of the fundamental common values of the EU.