General Franks was commissioned a second lieutenant in 1967 as a distinguished graduate of the Artillery Officer Candidate School, Fort Sill, Okla. After an initial tour as a battery Assistant Executive Officer at Fort Sill, he was assigned to the 9th Infantry Division, Republic of Vietnam, where he served as Forward Observer, Aerial Observer, and Assistant S-3 with 2nd Battalion, 4th Field Artillery. He also served as Fire Support Officer with 5th Battalion (mechanized), 60th Infantry during this tour.
In 1968, General Franks returned to Fort Sill, where he commanded a cannon battery in the Artillery Training Center. In 1969, he was selected to participate in the Army's "Boot Strap Degree Completion Program," and subsequently attended the University of Texas, Arlington, where he graduated with a degree in Business Administration in 1971. Following attendance at the Artillery Advance Course, he was assigned to the Second Armored Cavalry Regiment in West Germany in 1973 where he commanded 1st Squadron Howitzer Battery, and served as Squadron S-3. He also commanded the 84th Armored Engineer Company, and served as Regimental Assistant S-3 during this tour.
General Franks, after graduation from Armed Forces Staff College, was posted to the Pentagon in 1976 where he served as an Army Inspector General in the Investigations Division. In 1977 he was assigned to the Office of the Chief of Staff, Army where he served on the Congressional Activities Team, and subsequently as an Executive Assistant.
In 1981, General Franks returned to West Germany where he commanded 2nd Battalion, 78th Field Artillery for three years. He returned to the United States in 1984 to attend the Army War College at Carlisle, Penn., where he also completed graduate studies and received a Master of Science Degree in Public Administration at Shippensburg University. He was next assigned to Fort Hood, Texas, as III Corps Deputy Assistant G3, a position he held until 1987 when he assumed command of Division Artillery, First Cavalry Division. He also served as Chief of Staff, First Cavalry Division during this tour.
His initial general officer assignment was Assistant Division Commander (Maneuver), First Cavalry Division during Operations Desert Shield/Desert Storm. During 1991-92, he was assigned as Assistant Commandant of the Field Artillery School at Fort Sill. In 1992, he was assigned to Fort Monroe, Va. as the first Director, Louisiana Maneuvers Task Force, Office of Chief of Staff of the Army, a position held until 1994 when he was reassigned to Korea as the CJG3 of Combined Forces Command and U.S. Forces Korea.
From 1995-97, General Franks commanded the Second Infantry (Warrior) Division, Korea. He assumed command of Third (U.S.) Army/Army Forces Central Command in Atlanta, Ga. in May 1997, a post he held until June 2000 when he was selected for promotion to general and assignment as Commander in Chief, United States Central Command.