The article deals with the administrative arrangement of Ljubljana and the gradual formation of five urban municipalities during the period of socialism. Ljubljana experienced the most administrative changes between 1952 and 1963. The introduction of the communal system strongly influenced the development of Ljubljana. Five municipalities gradually formed in its territory: Bežigrad, Center, Moste - Polje, Šiška and Vič - Rudnik. Since Ljubljana was administratively divided into several municipalities, its development was decentralized despite the establishment of a city council with rights in the development of the city as a whole. More or less extensive rural areas joined the new municipalities. Connecting with rural areas was the result of the political decision to eliminate social and class differences as well as the differences between the city and the countryside.