Historically, credit unions were preceded by widespread development of credit cooperation in many countries of Europe and America. Most modern credit unions represent specialized consumer cooperatives of citizens associated by the principle of social community: place of work, place of residence, profession, or any other shared interest. Like the credit cooperatives, credit unions form associations of a higher level, which are called corporate credit unions. Is necessary that all shareholders of the credit union were members of a single community, would know each other well enough to enjoy mutual trust. Among the U.S. credit unions, there are three groups that differ in terms of assets, shareholders, and business services. In the case of default the shareholder - individual will respond with its property and, in addition, is jointly and severally liable with the credit union's commitments. Historically, credit unions have grown from the experience of credit cooperatives, but they took the experience of organizations of mutual aid of citizens by moving methods of social self-protection from labor and toward consumption. Credit unions base their activities on savings of shareholders, their shares and savings contributions, which make up the fund of mutual financial assistance - a source of cash loans to shareholders.