Historically, credit unions were preceded by widespread development of credit cooperation in many countries of Europe and America. Like the credit cooperatives, credit unions form associations of a higher level, which are called corporate credit unions. Is necessary that all shareholders of the credit union were members of a single community, would know each other well enough to enjoy mutual trust. To reduce the risk of default on loans members of the credit union shall the joint guarantee. 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. A potential new member of a credit union must submit a recommendation of shareholders in which the referee becomes a warrant of a future member of the credit union.