Principles of cooperative democracy and interaction were adequate to the purposes for which people joined credit unions. Among the U.S. credit unions, there are three groups that differ in terms of assets, shareholders, and business services. To reduce the risk of default on loans members of the credit union shall the joint guarantee. The relationship of shareholders with credit union are not client-based, they are co-operative, based on different principles and standards, in particular, on the principles of the law of obligations. In the credit union compensation for use of the loan (interest) is a source of compensation for savings. The value of credit unions is not limited to the role of the economic agent - they are an important element of the social structure and a factor of social stability and progress.