The purpose of the article is open to debate. It presents the main conclusions from a study made in March 2017 for the Office of Analysis and Expertise of the Senate of the Republic of Poland on the merits of changes in the territorial division of the Warsaw Metropolitan Area. In this study was carried out a synthesis of the research conducted mainly by the author on the development of Warsaw Metropolitan Area and the Mazowieckie voivodship, including the impact of the capital and delimitation of its functional urban area. In its summary were formulated the most important conclusions, arguing for finding a compromise solution, aimed at establishing a new administrative division system, taking into account both the daily urban system, spatial cohesion needs, and the interests of residents and entrepreneurs. Due to the importance of the area, including Warsaw’s functions as a capital city, the conclusions apply to the whole Poland.