U.S. Army Lt. Col. Mark Bailey, U.S. Army Training and Doctrine Command Special Troops Battalion outgoing commander, thanks his family and leaders for their support during a change of command ceremony at Joint Base Langley-Eustis, Va., Feb. 9, 2018. Bailey became the first commander of the STB in May 2015. (U.S. Air Force photo by Staff Sgt. Teresa J. Cleveland)