In 2019 Poland celebrated the 30th anniversary of political and economic transition. Although, 1989 was a year of unprecedented changes, the transformation of the economic system, which includes the development of different institutions, did not happen at once. Instead, it was a long-term process initiated at the beginning of communism in 1944. This paper is an attempt to analyze the development of Polish economic system since the early days of centrally-planned economy until 2019. A special focus is given to the key policies introduced by each government which were determining the institutional arrangements in different periods. The analysis includes also the effects of those changes on the country’s economic performance and well-being of the society. As the information presented in this paper comes from a variety of sources, it includes opinions on those effects presented by different economists which are not always coincident. In such cases both views are being discussed. The last part summarizes the characteristics of main institutions shaping Polish economy in three different periods of time.