Stephen “Sully” Sullivan became the assistant chief of Army Reserve, Office of the Chief of Army Reserve, on Aug. 23, 2026. Sullivan was selected to the Senior Executive Service in August 2019.
As ACAR, Sullivan serves as the primary advisor to the chief of Army Reserve for the development of plans, policies, budgets, and training programs for the management of the Army Reserve's troop program unit, individual mobilization augmentee, and Active Guard/Reserve programs worldwide. He assists the CAR to prepare an annual posture statement for the United States Congress on the state of America's Army Reserve to mobilize and deploy in support of the total Army and joint force. He provides guidance and oversight for the OCAR staff of 400 military, civilian, and contract personnel performing professional, technical and administrative functions.
His previous positions include: chief financial officer and director for resources, installations, and materiel for OCAR. In this role, he was responsible for the oversight of the CAR’s Title 10 responsibilities for four separate appropriations: reserve personnel, Army (RPA); operation and maintenance, Army Reserve (OMAR); military construction, Army Reserve (MCAR); and the National Guard and reserve equipment account (NGREA) totaling $9.3 billion.
As the CFO/DRIM, he also oversaw the real property accountability, sustainment, restoration, and modernization; equipping; and logistics requirements for 172,000 Soldiers and 9,900 Civilians supporting 2,161 units, 5 installations, and 742 separate facilities operating in all 50 states, 5 U.S. territories, and 24 countries.
Prior to joining OCAR, Sullivan served as the associate director for military operations in the Office of the Under Secretary of Defense (Comptroller), where he was responsible for the oversight of the Operation and Maintenance and Working Capital Fund accounts of the departments of the Army, Navy and Air Force. The $208 billion annual budget request resourced the training, organic and depot maintenance, supplies and equipment, civilian manpower, installation support, and operations (including overseas contingency operations) which sustain the readiness of the military departments and the global operations of the combatant commands in support of the national defense strategy.
Previously in the OUSD(C), he served as the principal financial analyst and program manager for the $4.7 billion Afghanistan Security Forces Fund annual funding program, which resourced the equipment, training, infrastructure and sustainment requirements of the Afghan National Defense and Security Forces consisting of the 382,000 members of the Afghan National Army, National Police, Air Force and Special Security Forces.
Sullivan attained the rank of colonel and retired from the U.S. Army in 2017 at the culmination of a 23-year active duty career as an aviation and financial management officer. His service includes two yearlong combat deployments in support of Operation Iraqi Freedom (Camp Arifjan, Kuwait) and Operation Enduring Freedom (Kandahar Airfield, Afghanistan) and assignments with the 3rd Infantry Division (Fort Stewart, Geogia and Kandahar, Afghanistan), the 18th Financial Management Center (Fort Bragg, North Carolina and Camp Arifjan, Kuwait), the 10th Mountain Division (Fort Drum, New York), and the 25th Infantry Division (Wheeler Army Airfield, Hawaii).
He is a graduate of the Army Leadership, Excellence, and Development (LEaD) Program - Intermediate Course, the Advanced Professional Executive (APEX) Senior Executive Service Orientation Program, the U.S. Army Command and General Staff College – Intermediate Level Education, the Aviation Officer Basic & Advanced Courses, Initial Entry Rotary Wing Training, and the UH-60 Aircraft Qualification Course. His awards and qualifications include the Legion of Merit, the Bronze Star Medal (2nd Award), the Army Aviation Association of America – Order of Saint Michael (Bronze Award), Distinguished Member of the Regiment of the U.S. Army Finance Corps Association, as well as the Senior Army Aviator, Parachutist, Air Assault, and Army Staff and Joint Chiefs of Staff Identification Badges.
Mr. Sullivan has attained the Department of Defense Financial Management Certification – Level 3 and Certified Defense Financial Manager with Acquisition Specialty (CDFM-A) qualifications. He holds a Master of Business Administration from the Georgetown University McDonough School of Business, as well as Bachelor of Science degrees from Grove City College in Physics and Slippery Rock University of Pennsylvania in Business Administration – Accounting.