The article aims to identify and discuss the main resources shaping the competitiveness of Polish enterprises, including their international competitiveness. The research involves an empirical study conducted on a sample of Polish enterprises displaying above-average growth. The research method used is the multiple case-study approach, which makes it possible to gather qualitative data on the resources held by the analyzed enterprises. The results are presented in accordance with the proposed typology of resources with a division into tangible and intangible resources as well as combinations of these two. The article discusses in detail the main characteristics of the resources involved in terms of enterprise competitiveness. The author concludes that, first, Polish companies with above-average growth rates have resources whose features fully meet the resource theory as well as the so-called knowledge-based view. Second, the research shows that it is not only resources themselves but also idiosyncratic ties between them that shape the competitive advantage of the analyzed companies, Śliwiński says. Third, resources tend to play a different role in companies with above-average growth rates compared with the general population of companies. The impact of resources on the competitiveness of the surveyed enterprises was significantly different than in the case of companies not selected specifically in terms of above-average growth, the author says. Furthermore, the research revealed that Polish firms have largely grown similar to their counterparts in more developed countries in terms of the structure, hierarchy and key features of the resources used, Śliwiński says.