The number of shareholders of a credit union is limited and formalized by a list. Limit of the number is defined by the assembly and such assembly establishes the charter. The uniqueness of credit unions is that they put together the principles and benefits of financial cooperatives, consumer cooperatives and mutual aid funds, born once by trade unions. Credit union is created by a group of members who pursue a common interest. Agreeing to make regular contributions, they create a fund from which can borrow money for investments and replenishment of working capital at favorable interest rates. Specialization of credit unions to provide financial services to its shareholders requires a particularly strict regulation of membership and acceptable activities. Credit union promotes the effective conservation of personal funds of its members, giving them the loans from the funds of the credit union, as well as the sharing of savings in education, housing, health care and other programs of social support and social development of its members. At the organization of the credit union it is important that people know each other and know the extent to which each of them is trustworthy. Among the U.S. credit unions, there are three groups that differ in terms of assets, shareholders, and business services. Until the mid-XX century, credit unions in the United States had little assets that did not exceed, as a rule, 100 thousand dollars In the UK, credit unions are a source of financing of people groups. This tool is not widely used.