The article is aimed at analyzing the effects of the European Union regional policy to remove the disparities in the development of its member states. The analysis makes use of both European Commission reports and research carried out by the European scientific institutes in order to answer the question why the differences in the level of the member states' and particular regions' development do not decrease at all (regions), or decrease at a very slow pace (countries). It is not easy to answer the question due to the lack of tools accurate enough to measure the results of that regional policy. The present analysis enables the authoress making the following conclusions: 1) Funds spent on the cohesion policy should support the improvement of the quality of administration and established law to a greater extent than they have so far; 2) The effects of the cohesion policy in Poland will determine the future cohesion policy in the European Union; 3) It seems that Polish regions are strongly motivated and well prepared to absorb the funds offered within the cohesion policy. This potential should be used to increase Polish influence on the course of the European Union regional policy reform.