Corporate credit unions are united on a cooperative basis in the Central Credit Union (US Central Credit Union). 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. The uniqueness of credit unions is that they put together the principles and benefits of financial cooperatives, consumer cooperatives and mutual aid funds, born once by trade unions. First central bank of credit unions appeared in 1876. Credit unions began to appear rapidly in many European countries. Cooperation between credit unions, how they would not have been named, took place always, from the moment when the movement moved outside one credit union. Credit unions, like today's credit unions, emerged in the 19th century in Germany as a result of crop failure and famine. 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. Corporate alliances are intermediaries between credit unions and financial markets.