The work is dedicated to research of externalities, positive effects of a meso-level of international integration formations represented by network structures of intra-industrial and inter-industrial cooperation in a form of cross-border cluster systems.
Major objectives of the work are, as follows: to prove statement, that international integration schemes in the form of cross-border clusters generate positive externalities which catalyze euroregional competitiveness; to apply newer approaches to revealing and systematization of cluster externalities; to emphasize special part played by network externalities and effect of «knowledge spill-over» within the cluster framework being of utmost importance for formation of cross-border cluster systems and increasing their competitiveness. Basing on the above research it seems reasonable to formulate specifics of cluster model in cross-border cooperation as the most adequate in modern conditions of global economy development and current stage of integration of Ukraine in general and, in particular, within the framework of the EU economic space. 

externalities, synergy effect, cross-border cluster system, European integration, euroregion, innovations, competitiveness