Secretary Treasurer (title changed to Executive Director in 1977)

Cecil R.Chamberlain, 1920-1924
Charles A. Timm, 1924-1926
Roscoe C. Martin, 1926-1930
Harvey Walker, 1930-1936
John W. Manning, 1936-1946
Franklin L. Burdette, 1946-1948
Elwin A. Mauck, 1948-1952
Joseph R. Starr, 1952-1954
Don L. Bowen, 1954-1960
Franklin L. Burdette, 1960-1975
Howard Penniman, 1975-1991
Karl H. Cerny (acting), 1991-1992
James I. Lengle, 1993-