After graduating from North Georgia College ROTC in June 1963, Major General Guest entered service as an Infantry second lieutenant. As a company grade officer he served as a platoon leader with the Berlin Brigade in Germany (1963-65) and commanded the 600^th Quartermaster Company, XVIII Airborne Corps at Fort Bragg, (1968-69).

General Guest served three separate tours in Southeast Asia – as a battalion level Operations Officer and Military Assistance Command-Vietnam advisor in South Vietnam, in 1966 and 1970, respectively; and Division Chief with the Defense Attaché Office in Laos, in 1975, at war’s end. Other significant positions included S3 and Executive Officer with the 4^th Infantry Division, Division Support Command (DISCOM), Fort Carson; also Commander, 1^st Supply and Transportation Battalion and Assistant Chief of Staff/G4 for the 1^st Infantry Division, Fort Riley.

Following graduation from the Naval War College in 1984, General Guest served three years in Office of the Deputy Chief of Staff, Logistics, then commanded the 101^st DISCOM, Fort Campbell (1987-89). He was Deputy Commanding General, 21^st Theater Army Area Command (TAACOM) in Germany when Iraqi forces invaded Kuwait and went to Southwest Asia in September 1990 to become Deputy Commanding General, 22^nd TAACOM for Operation Desert Shield, and later served with the XVIII Airborne Corps during Operation Desert Storm.

Afterwards, General Guest commanded the 3^rd COSCOM in Wiesbaden, Germany, and was Deputy Chief of Staff for Logistics, United States Army Europe and Seventh Army, from 1991 to 1993. Then to Fort Lee where he became the 43^rd Quartermaster General of the Army, and, prior to his retirement in 1998, Commander of the U.S. Army Combined Arms Support Command. He has been described as a Log Warrior second to none, and “the consummate Quartermaster.”