The EU has been leaning towards evidence-based policymaking with the aim of ensuring coherence between industrial, environmental, climate, and energy policy. It focuses on supporting the development of a business environment which would enable sustainable growth, job creation, and innovation. It is generally agreed upon that, at the current level of development, the EU should focus on boosting innovations and theory and practice deliver an array of suggestions on how to achieve this goal. Among them clusters and cluster-led development play a prominent role. Poland inherently follows this belief and has introduced cluster policy to its policy mix by supporting cluster initiatives and cluster organizations. The objective of the paper is to investigate the evolution of cluster policy in Poland, identify its success factors, and propose recommendations for cluster policy. This case study of cluster policy in Poland is based on a series of in-depth interviews as well as secondary data. The conclusions resulting from this case study indicate that adoption by the government of a cluster policy at the national level and implementation of a comprehensive strategy for cluster development at regional and national levels is a basic condition for cluster policy success. Positive results can be achieved if public intervention is continuous and tailored to the needs of cluster organizations at different development stages with particular emphasis on the internationalization of cluster activities, which was a key measure highly evaluated by the respondents. The paper touches upon the timely issue of the future direction of cluster policy. The debate on it is accompanied by another debate on how to build an economic ecosystem capable of reaching sustainability goals.