Scott Air Force Base, located near Belleville, Illinois, is a United States Air Force installation. Established in 1917 as Scott Field, it was one of the initial Air Service training camps during World War I. The base serves as the headquarters for Air Mobility Command (AMC) and the U.S. Transportation Command, a Unified Combatant Command. The 375th Air Mobility Wing operates as the host unit, with additional units including the Air Force Reserve Command's 932nd Airlift Wing and the Illinois Air National Guard's 126th Air Refueling Wing. The base employs approximately 13,000 personnel, comprising active-duty Air Force, civilians, and Air National Guard and Reserve members. Its airfield is shared with civilian operations, known as MidAmerica St. Louis Airport, which has operated as a Joint Use Airport since November 1997. Historically, Scott Field transitioned from an aviation training field to a lighter-than-air station in 1921, then became a technical training installation, primarily for radio operators, during World War II. After the U.S. Air Force became a separate service in 1947, Scott AFB transitioned to an air mobility mission in 1957 with the relocation of Military Air Transport Service (MATS) headquarters. The base's aeromedical evacuation mission expanded with the 375th Aeromedical Airlift Wing. Current operations include aeromedical airlift, operational support airlift, and air refueling missions, supported by aircraft such as the C-40C Clipper, C-21A Learjet, and KC-135R Stratotanker. Recent developments include the addition of cybersecurity squadrons.