The social and political transitions taking place in Central and Eastern Europe post-1989 allowed Poland to develop cross-border cooperation with neighbouring counties. At local-government level in particular, the Czech Republic then became a key partner. Today, the Polish-Czech borderland resembles those between Poland and Germany, and between Poland and Slovakia, in constituting a model example of innovative cross-border cooperation. While the area first played hosted to Euroregions, it later also fell within European Groupings of Territorial Cooperation. And while collaboration between one local authority and another over the border has evolved particularly dynamically, as-yet untapped potential would seem to remain. Overall, this article seeks to analyse the actors currently operating across the Polish-Czech border, from a political-science perspective. These are Euroregions (of Nysa, Glacensis, Pradziad, Silesia, Cieszyn Silesia and the Beskids), as well as European Groupings of Territorial Cooperation (of Tritia and Novum), and selected units at local government level. The analysis of the transboundary entities, and those engaging in cross-border activity was of a genetic, structural and functional nature, and this facilitated the identification of similarities and differences between the actors concerned, making clear what their specifics are, and what the prospects for cooperation.