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.). Representative organization, leading the coordination work in the field of development of both global and national credit union movement is the World Council of Credit Unions (WOCCU) established in 1971 (headquartered in Madison, USA). 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. Until the 70's there was a proliferation of the U.S. credit unions due to the increase of their number and the number of shareholders, although it must be acknowledged that there was also and a qualitative growth. National Credit Union Insurance Fund was created by Congress in 1970 to insure deposits of credit union members in the amount of 100 thousand dollars. The relationship of shareholders with credit union are not client-based, they are co-operative, based on different principles and standards, in particular, on the principles of the law of obligations. 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. Unlike banks, in order to use the services of a credit union, you have to become its member, having written an application and having paid thus shares and membership fee.