Mo. Rev. Stat. § 64.520
Such county planning commission shall consist of the county highway engineer or head of the highway department, and one resident of the county appointed by the county commission, from the unincorporated part of each township in the county, except that no such resident shall be appointed from a township in which there is no unincorporated area. The township representatives are hereinafter referred to as appointed members. The term of each appointed member shall be four years or until a successor takes office, except that the terms shall be overlapping and that the respective terms of the members first appointed may be less than four years. The term of the county highway engineer shall be only for the duration of the engineer's tenure of official position. All members of the county planning commission shall serve as such without compensation, except that an attendance fee as reimbursement for expenses may be paid to the appointed members of the planning commission in an amount, as set by the county commission, not to exceed twenty-five dollars for each meeting. The planning commission shall elect its chairman, who shall serve for one year.
§ 64.520, RSMo