In the U.S., credit unions have a clear organizational structure. All credit unions belong to one or the other parent credit union (there are 35 of them in the U.S.). Corporate credit unions are united on a cooperative basis in the Central Credit Union (US Central Credit Union). National Credit Union Administration (NCUA) - an independent federal agency, based in Washington (State of Columbia), established by the U.S. Congress to oversee the federal credit union system. To get a loan in the credit union a shareholder must be not only a formally adopted there, but necessary pay in cash contributions, the amount and order of payment of which approved by the General Assembly and fixed by the charter. The main advantage of credit unions consists in transparency, controllability, governance for shareholders. Credit unions historically formed as a special form of social support, initially taken upon themselves the social mission of protecting the interests of citizens in the field of financial services.