Historically, credit unions were preceded by widespread development of credit cooperation in many countries of Europe and America. Like any financial institution, credit unions have the financial resources. 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. 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. Over 30% of the assets of credit unions are investments in government securities, certificates of deposit of banks and savings loan associations, as well as in the parent credit unions, and other risk-free investments. To increase the number of credit unions in 1979 was adopted the corresponding law that serves as the legal basis of their activity.