The article analyzes the premises and areas of tripartite cooperation, including the Republic of Moldova, Ukraine and Romania in the Lower Danube Euroregion. For the European Union, cross-border cooperation becomes the most important medium for the dissemination of its norms and standards on the neighboring states, and is of great economic importance, since it contributes to the formation of a "broad" Europe. For Ukraine and Moldova a major goal in the implementation of concrete cross-border cooperation projects with neighboring EU countries is European integration and endowing this process with more pronounced dynamism and constructivism.