Colonel Stephanie D. Vaughn was commissioned as a Chemical Officer upon graduation from Officer Candidate School class 1-91 on 18 January 1991. Her first duty assignment was as an Executive Officer in 3d Corps Support Command, Wiesbaden, Germany. | Her subsequent duty assignments include: Platoon Leader, 95th Chemical Company, Vilseck, Germany; 03 Operations Officer, Headquarters, Southern European Task Force, Vicenza, Italy; Chemical Officer, 555th Engineer Group, Fort Lewis, Washington; Company Commander, D Company, 82d Chemical Battalion, Fort McClellan, Alabama; Company Commander, D Company, 82d Chemical Battalion, Fort Leonard Wood, Missouri; Brigade Training Officer, 3d Chemical Brigade, Fort Leonard Wood, Missouri; Senior Nuclear Engineer, Armed Forces Radiobiology Research Institute, Bethesda, Maryland; Director of Operations, Armed Forces Radiobiology Research Institute, Bethesda, Maryland; Nuclear Physicist, United States Army Nuclear and Combating Weapons of Mass Destruction Agency, Fort Belvoir, Virginia; Executive Officer Nuclear Posture Review, Office of the Deputy Assistant Secretary of Defense for Nuclear and Missile Defense Policy, Pentagon, Washington, D.C.; Nuclear Threats Branch Chief, Defense Threat Reduction Agency, Fort Belvoir, Virginia; Deputy Director, Nuclear Technologies Department, Defense Threat Reduction Agency, Fort Belvoir, Virginia; and Acting Director, Nuclear Technologies Department, Defense Threat Reduction Agency, Fort Belvoir, Virginia. | Her military education consists of: Chemical Officer Basic Course, Chemical Officer Advanced Course, Army Medical Department Basic Course, Combined Arms Services and Staff School, United States Army Command and General Staff College and the United States Army War College.