Corporate credit unions are united on a cooperative basis in the Central Credit Union (US Central Credit Union). 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. Specialization of credit unions to provide financial services to its shareholders requires a particularly strict regulation of membership and acceptable activities. 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. Membership in the credit union forms responsible citizens and conscientious attitude to their obligations as a norm of behavior, identify the value of a decent man's reputation in the business turnover. The supreme body of the World Council of Credit Unions is the Assembly, which elects the president and the board of directors of WOCCU. Credit cooperatives and credit unions exist in many different forms. The main differences relate to the nature of the membership and the opening of a credit institution.