Small and medium-sized enterprises of the European union are new job generators and are considered the backbone of the economy, therefore investment in the development of their international competitiveness is considered to be extremely necessary and important. The integration of small and medium-sized enterprises on the global market has encouraged them to develop international activities. An analysis of international competitiveness indicators found that the international activities of small and medium-sized enterprises and their investment in competitiveness factors stimulate the development of their international competitiveness in the European union's internal market. Some of the important determinants that influence the development of international competitiveness of SMEs are innovation and the information and communication technology structure. To make companies competitive, it is necessary to invest in these factors. The European union through its instruments and measures affects the development of competitiveness of small and medium-sized enterprises. The competitive problems faced by SMEs are economies of scale, accelerated technology development, segmented market factors, policies and institutions important for production. One of the fundamental objectives of the European union's cohesion policy is to improve the competitiveness of small and medium-sized enterprises. Demographic trends, the emergence of the United Kingdom from the European union, technological change, globalization and liberalization are some of the trends and challenges that affect the development of small and medium-sized enterprises.