Cross-border cooperation, which has existed in Western Europe since the 1950s, has developed in Central and Eastern Europe only after 1990. This paper provides basic information about the development of cross-border cooperation and the formation of Euroregions in the Slovak Republic. This process is at the stage of formation and institutionalisation, due to legislative obstacles. The stage of realising concrete forms of cooperation can begin only after the stabilization of new regional self-government. The spatial differentiation and regionalization of Slovak border regions is accounted for, in this study, primarily by the relations between the given territory to that on the other side of the State border.