Okla. Stat. tit. 19 § 866.1
For the purpose of cooperating with the State of Oklahoma in conserving the natural resources of the state, and in promoting the health, safety, peace, morals and general welfare of the people of the state, there may be provided in any county of the State of Oklahoma in which there is no city having a population of more than two hundred thousand (200,000), according to the last preceding Federal Decennial Census or any future federal census, one or more city and county planning and zoning commissions, in the manner herein provided, and for the purpose there is hereby authorized to be created in each of such counties city-county cooperative planning commissions, which shall be designated "metropolitan area planning commission", and a county board of adjustment with the respective powers and duties as set out in this act. In the execution of its purposes, such metropolitan area planning commission shall function as an advisory, consultative and coordinating agency, established to harmonize its planning activities with the planning activities of departments, agencies and instrumentalities of federal, state and local government; and to stimulate public interest and participation in the development of the area. As used in Sections 866.1 through 866.36 of this title, the word "city" includes incorporated towns.
Okla. Stat. tit. 19, § 866.1