Membership in the credit union is voluntary and is open to all citizens bound by with joint work or residence, who wished to create a credit union to use its services and are willing to take on relevant commitments and responsibilities. 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). When organizing the credit union it is important that people know each other and know the extent to which each of them is trustworthy. The main advantage of credit unions consists in transparency, controllability, governance for shareholders. 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). 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. Today, the World Council of Credit Unions is represented as members four regional confederations and twelve national associations. 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.