Credit union is created by a group of members who pursue a common interest. Agreeing to make regular contributions, they create a fund from which can borrow money for investments and replenishment of working capital at favorable interest rates. 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. Income derived from the provision of services to its members, does not become the profit of credit union and is distributed among its members in proportion to their savings. 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.