Missouri Constitution
Article IV - Executive Department
Section 17 Elective state officers—time of election and terms—limitation on reelection—selection of department heads—removal and qualifications of appointive officers.

The governor, lieutenant governor, secretary of state, state treasurer and attorney general shall be elected at the presidential elections for terms of four years each. The state auditor shall be elected for a term of two years at the general election in the year 1948, and his successors shall be elected for terms of four years. No person shall be elected governor or treasurer more than twice, and no person who has held the office of governor or treasurer, or acted as governor or treasurer, for more than two years of a term to which some other person was elected to the office of governor or treasurer shall be elected to the office of governor or treasurer more than once. The heads of all the executive departments shall be appointed by the governor, by and with the advice and consent of the senate. All appointive officers may be removed by the governor and shall possess the qualifications required by this constitution or by law.

Source: Const. of 1875, Art. IV, Sec. 2. (Amended August 4, 1970)