Fund of Mutual Financial Aid of the credit union can be extended by sponsorship contributions from businesses, organizations, including on a returnable basis. 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. 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. Credit unions of the open type are still controlled by their members, but at the same time provide services to people who are not its members (external customers). The relationship between credit unions and shareholders arise from the membership and are not customer relationship.