The determinants of SMEs’ competitiveness and, in particular, the constraints faced by SMEs, as well as the implications of the barriers for a firm’s growth have been investigated by a great number of researchers. Despite the popularity of the studies focused on SMEs competitiveness this topic is not losing its relevance, since SMEs are backbone of national economies. The issue is of even greater importance for post-transition economies. In this paper, we argue that intracluster cooperation, which should epitomise the genuine and fully fledged cluster, provides cluster firms, in particular SMEs, with advantages and thus can assist SMEs in upgrading their competitiveness. Special role play in this respect also dedicated cluster organisations. The conceptual part of the paper is accompanied by empirical considerations. Best practices from selected Polish clusters dominated by micro, small and medium enterprises are presented