Mo. Rev. Stat. § 67.360
The political subdivisions of the state of Missouri are authorized to utilize such services as may be provided by the state division of purchasing, within the limits of the appropriation of that state agency for this purpose. The governing bodies of the state's political subdivisions may require all offices and individuals of their political subdivision to conform to the requirements, as promulgated by the governing body of the political subdivision involved in the purchasing agreement entered into with the state agency. Governing bodies of all political subdivisions of the state are hereby authorized to enter into agreements with the state agency covering the purchase of materials, supplies and equipment meeting their legal needs and are authorized to delegate to the state agency such functions relating to the purchases as shall be covered by the cooperative agreement with the state agency.
§ 67.360, RSMo