European integration as a basis for converging political and legal systems of Ukraine and the European Union

The article deals with the essence and peculiarities of various theories and approaches to the study of integration within European integration Communities. It provides the analysis of theoretical approaches and concepts by various schools on the definition of “integration”, preconditions for the emergence and development of the European integration placing special emphasis on the essence and content of the European legal integration theory. The author focuses on describing legal integration theory within the European integration Communities.