Corporate credit unions are united on a cooperative basis in the Central Credit Union (US Central Credit Union). Most modern credit unions represent specialized consumer cooperatives of citizens associated by the principle of social community: place of work, place of residence, profession, or any other shared interest. Activity of the credit union consists of organizing mutual financial assistance by meeting the needs of its members in the services of saving and obtaining loans. Credit unions encourage savings of citizens, setting compensation payments (interest) on savings and provide from these savings loans to their members. Unlike banks, in order to use the services of a credit union, you have to become its member, having written an application and having paid thus shares and membership fee. Unlike banks credit unions limit their activities to a closed circle of people.