A credit union in Melville is a cooperative financial institution that is owned and controlled by its members and operated for the purpose of promoting thrift, providing credit at competitive rates, and providing other financial services to its members. Many credit unions exist to further community development or sustainable international development on a local level. They are typically smaller than banks, and are generally not-for-profit cooperative institutions. Credit unions in Melville have an unusual organizational structure, which attempts to solve the principal-agent problem by ensuring that the owners and the users of the institution are the same people. In any case, credit unions cannot accept donations and must be able to prosper in a competitive market economy.