Included within the broad concept of a corporation are several special subtypes. The corporation's stock may be held by only a small number of individuals; such a corporation is known as a partnership and its owners are partners. In other corporations, known as cooperatives, the stockholders may share some additional function with respect to the corporation. In workers' cooperatives, for example, the stockholders are also the employees of the corporation. In consumers' cooperatives, the corporation's stockholders are also the expected consumers of its products. Despite the collectivistic connotations of the term "cooperative," such structures are fully possible under the flexible umbrella of the free market. Cooperatives are subject to the same principles of operation as any other corporation. The functions of ownership, production, and consumption can still be separated conceptually, even though some individuals may be associated with more than one of these functions.