Colonel Monica Washington graduated from the United States Military Academy and received her commission as a Second Lieutenant in the Transportation Corps in 1994.

Colonel Washington has served in various leadership positions throughout her career. Her initial assignment was with the 548th Combat Service Support Brigade, 10th Mountain Division, Ft. Drum, New York, where she served as platoon leader, motor/rail Transportation Officer, and Battalion S1. After her initial assignment, Colonel Washington attended the Combined Logistics Officer Advance Course at Fort Lee, Virginia. Upon completion, she served with the 49th Movement Control Battalion as a Movement Control Officer, Fort Hood, Texas and the 180th Transportation Battalion, Company Commander, Headquarters and Headquarters Detachment. After command, she participated in the Training with Industry Program, at the Federal Express (FEDEX) Headquarters in Memphis, Tennessee.

In 2002, Colonel Washington was assigned to Joint Forces Command located in Norfolk, Virginia. Following her time in Virginia, Colonel Washington served as the Executive Officer, 836th Transportation Battalion in Yokohama, Japan. Colonel Washington departed Japan to attend the Command and General Staff College (CGSC) in Fort Leavenworth, Kansas. After graduation, she deployed with the 595th Transportation Terminal Group to Camp Arifjan, Kuwait where she served as the Chief of Terminal Operations. Upon her return, Colonel Washington was assigned to the U.S. Army Transportation Command, Scott Air Force Base, Illinois where she served in the J3 as the Chief, Training and Simulations, J3 Executive Officer and EUCOM/AFRICOM/SOCOM Branch Chief. Colonel Washington returned to Japan to serve as the G4, US Army Japan/I CORPS (FWD), Camp Zama, Japan.

Upon completion of this assignment, Colonel Washington assumed command of Baton Rouge Recruiting Battalion in Baton Rouge, Louisiana. After command, Colonel Washington attended the Army War College Fellowship Program at Columbia University, New York, New York. Her previous assignment was as the G3, 19th Expeditionary Sustainment Command.

Colonel Washington's awards and decorations include the Legion of Merit; Defense Meritorious Service Medal (with Oak Leaf Cluster), the Meritorious Service Medal (with two Oak Leaf Clusters), the Joint Service Commendation Medal, the Army Commendation Medal (with Oak Leaf Cluster), and the Army Achievement Medal (with two Oak Leaf Clusters).
Colonel Washington assumed command of the United States Army Garrison -- Yongsan (Area I/II) on 22 June 2018 and currently serves as the Garrison Commander.