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. Specialization of credit unions to provide financial services to its shareholders requires a particularly strict regulation of membership and acceptable activities. 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. The relationship between credit unions and shareholders arise from the membership and are not customer relationship. 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.