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. Today in the UK there are about 700 credit unions with assets exceeding 200 million pounds. Among the U.S. credit unions, there are three groups that differ in terms of assets, shareholders, and business services. Credit unions are competitors of savings institutions, adding interest on deposits of members. This applies to the shares, as well as to additional funds transferred to the account in the credit union. Historically, credit unions have grown from the experience of credit cooperatives, but they took the experience of organizations of mutual aid of citizens by moving methods of social self-protection from labor and toward consumption. Shareholders in corporate organizations are basic credit unions, besides the same union can be a shareholder of several corporate organizations. Credit unions historically formed as a special form of social support, initially taken upon themselves the social mission of protecting the interests of citizens in the field of financial services. Worldwide credit union movement is represented by regional confederations and national organizations within the World Council of Credit Unions.