Mo. Rev. Stat. § 182.080
The county library board of trustees may contract with the body having control of a public library for assistance in the operation of a free county library under such terms and conditions as may be stated in the contract, or it may contract with the body having control of a public or a school library or any other library to furnish library service to the people of the county library district, under such terms and conditions as may be stated in the contract. The body having control of any library district may contract with any such county library board of trustees to provide library service to the people of the library district under such terms and conditions as may be stated in the contract. The county library board of trustees may contract with any other county library district under the terms outlined in sections 70.210 to 70.320. In case a contract is made for services by any library, the contracting library boards of trustees shall advise and consult together with regard to the management and disbursement of funds, and other policies relating to the proper management of the library.
§ 182.080, RSMo