Specialization of credit unions to provide financial services to its shareholders requires a particularly strict regulation of membership and acceptable activities. Members of credit unions place in credit unions usually free fund balances, ie those that remain after expenses devoted to education of children, the acquisition of new properties, additional pension benefits, etc. To reduce the risk of default on loans members of the credit union shall the joint guarantee. 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. In some cases, the initiators of credit unions can be trade unions, associations such as social support centers and others. The right to use the services of the credit union have only its members. 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. Today, the World Council of Credit Unions is represented as members four regional confederations and twelve national associations.