The cross-border nature of the region actualizes qualitatively new facets of vocational training, increasing the role of the only state higher education institution in the Ukrainian Danube region - Izmail State University of Humanities - an active participant in cross-border cooperation in the Lower Danube Euroregion. As a result of the conducted pedagogical discourse, which aims to identify the theoretical foundations of international relations in the context of their regional diversity, a corresponding contradiction has been established. It consists in the discrepancy between modern requirements for full consideration of cross-border and insufficient attention of researchers to the specifics of professional training as subjects of international relations. This has become our research task, and the coverage of some approaches to its solution is the purpose of this article. We proceeded from the understanding that in modern realities the competence of diplomacy is not just desirable, but an indispensable personal and professional quality. It is important to mention that this concerns professional diplomats as well as specialists in other subject areas. Our research attention, in particular, is focused on the process of vocational training of specialists who have chosen the type of profession «human – human», «human – nature». This is due to the actualization of at least two problems in the Ukrainian Danube region: increasing the efficiency of multicultural education and ensuring sustainable development in the context of environmental security. The content of this research was the intensification of European integration processes in the Ukrainian society and the enrichment of the traditions of good neighborliness as an important resource of interethnic tolerance in the multicultural Lower Danube Euroregion.