The 377th Theater Sustainment Command is a multi-functional unit that performs a dual mission. The first is mission command of assigned forces in order to provide the United States Army Reserve with trained and ready units and individuals that support geographic combatant command requirements. The second mission is to deploy and operate as the senior Army logistics headquarters capable of planning, controlling and synchronizing operational-level Army deployment and sustainment. The 377th TSC has more than 36,000 Soldiers and civilians in 34 states. The workforce is made up of approximately 80 percent Reserve citizen Soldiers, 10 percent represent the active component and about 10 percent are civilians. It is commanded by a major general (two-star) with six brigadier general (one-star) deputy commanders in its command structure.

The unit was activated In July 1942 as Headquarters and Headquarters Company, 12 Port of Embarkation, at Fort Dix, N.J. It was then converted, reorganized and redesignated the 12th Port Headquarters and Headquarters Company, and assigned to the Transportation Corps in November 1942. After an inactivation in 1946, the unit was redesignated Headquarters and Headquarters Company, 377th Transportation Major Port, and assigned to the Organized Reserve Corps in November 1948. Two weeks later, the 377th Transportation Major Port was activated in New Orleans. The unit has been a part of the New Orleans community since that time.

In September 1950 the 377th was called to Fort Eustis, Va., and stayed on active federal service until Oct. 10, 1952. From 1953 until 1963, the 377th remained in a Reserve status and experienced extensive growth and several changes in unit designation.

In December 1965, the unit was redesignated as the 377th Support Brigade under the Army Logistical Concept. On Oct. 16, 1979, it was renamed the 377th Corps Support Command and retained this designation until July 16, 1981, when it was designated as a Theater Army Area Command (TAACOM). On Oct. 1, 1998, the TAACOM wartime mission expanded and the unit designation was changed to the 377th Theater Support Command.

The 377th Theater Support Command was redesignated the 377th Theater Sustainment Command (TSC) and regionally aligned to U.S. Southern Command in September 2007. Since then, the 377th TSC has generated and globally deployed sustainment forces for multiple missions in support of Operation Enduring Freedom, Operation Iraqi Freedom and Operation New Dawn. Most recently, the 377th TSC provided earthquake relief in Haiti as part of Operation Unified Response in 2010 and provided assistance in the wake of Hurricane Sandy in 2012. As the Army transforms, the 377th TSC will continue to lead the way by integrating emerging technology with the best-trained and ready Soldiers to provide sustainment solutions to support any mission.