In more pragmatic areas the Communists altered the form of government, the social structure, and the economy. The 1948 Constitution established a form of government much like that of the Soviet Union and other communist-ruled states in that the government is structured to be the instrument through which the party runs the country. There is an interlocking of party and government positions that ensures party control over every facet of Romanian life. There are no competing political parties, but there are several mass organizations, thoroughly PCR dominated, in which the people are urged to participate. These include labor unions, youth leagues, women's organizations, and sports societies, which serve to involve the people in national and local affairs while the party hierarchy retains absolute authority in all areas. The 1948 Constitution was superseded by another in 1952 that brought no significant changes and did not greatly alter the structure that had been established earlier. The Constitution of 1965, however, changed the name of the country to the Socialist Republic of Romania, and, in communist jargon, this change was of particular importance because it signified that the transition from bourgeois capitalism to socialism had been achieved and that Romania could now proceed on its path toward communism. Significant also in the 1965 Constitution was the absence of any mention of the Soviet Union, which had been featured prominently in the previous documents as a model to be copied and as the liberator of Romania. The most prominent feature of the Romanian political system is its extreme centralization in both the party structure and the government organization. The people vote for their representatives at all levels of government from a single list of party-approved candidates. Local governments always look for direction from a higher level or from the center. The PCR has a similar pyramidal structure, the topmost organs being self-selecting and self-perpetuating. The concentration of power in the hands of the party hierarchy has prevented the rise of any overt opposition groups, and there has been no observable coalition of dissenters within the party ranks.