In the Strategy "Europe 2020", the European Union has set itself the goal of transforming economies that will achieve high employment rates, productivity and social cohesion. The European Commission, through its institutions, aims to promote the development of clusters in Europe, in particular with a view to fostering competitiveness and entrepreneurship, and promoting international cluster cooperation to facilitate the integration of European small and medium-sized enterprises into a global value chain. The paper provides a theoretical overview of the concept and importance of clusters as a model for the development of companies and their impact on competitiveness. Particularly, the aim is to explore the openness and readiness of organizations in the ICT sector of the Republic of Croatia to enter in clusters and the possibility of networking the ICT clusters in the existing cluster system and the contribution of such clusters to the growth of competitiveness. Based on the former research, initiatives, clustering policies in the EU, the impact of clusters on competitiveness and positive examples of clusters in the ICT sector of the European Union, support the thesis that clusters should be encouraged in activities that create high value added products and services. The cluster in the information and communication technology (ICT) can be a platform for improving the competitiveness of the ICT sector and economic growth and development. The paper is being explored the activities of clusters in the ICT sector in the Republic of Croatia, assuming that the improvement of cooperation and networking of existing clusters in the ICT sector in the Republic of Croatia contributes to the competitiveness of the companies themselves within the ICT cluster and the competitiveness of the Croatian ICT industry. In order to use the cluster potential in the ICT sector of the Republic of Croatia, it is necessary to support the strengthening of clusters at the government level, with the participation of all relevant institutions.