The article presents the results of a study of the reasons for rulings of the Polish courts in terms of the presence in them of references to common law. The analysis of the title issue is mainly of a qualitative nature with descriptive, systematic, and explanatory features. The research has focused on determining the functions played by the references to common law in judgments and on recognizing the  factors that rule or causally explain the practice of the courts referring to the given law system in their decisions. Some general regularities characterizing the discussed phenomenon have also been shown. Furthermore, quantitative findings on the scale, intensity, and dynamics of the references to common law in the reasons for judgments have been presented. Common law, which until now has been the subject of comparative studies of the Polish legal science, is increasingly drawing attention of the Polish courts as the law-applying bodies. Furthermore, the paper confirms the growing role of foreign law in the judicial decision-making process.