The operation of a franchise network is a method of doing business that is popular in a number of service activities, especially hotels, restaurants, and retail sales. Franchisees are independent legal units which sign a contract with another legal unit, the franchiser, to engage in an activity making use of trademarks, trading styles and marketing support provided by the franchiser, usually in return for a fee or a share of the profits. A franchise contract typically includes a number of restrictive clauses limiting the franchisee’s freedom of choice. The franchiser, in turn, offers scale economies without completely taking away the autonomy of the franchisee, for example by taking care of collective marketing. Franchise operators may or may not belong to the same enterprise group. Franchisees are deemed to be separate enterprises because they consist of a complete combination of factors of production, and they run the full entrepreneurial risk. Moreover, the definition of the enterprise requires autonomy but allows for this autonomy to be somewhat restricted ("a certain degree of autonomy" is required), and full accounts tend to be available only at the level of the separate franchisees. The franchiser is also regarded as a separate enterprise.