U.S. Army Reserve Command
Force Composition
Over 200 thousand Reserve Soldiers are ready to serve the Nation when needed.

Three different groups make up today’s Army Reserve: 
The Selected Reserve, the Individual Ready Reserve (IRR) and the Retired Reserve. 
Learn more about these groups, including the important role each plays in today’s Army.
Selected Reserve
The Selected Reserve is the most readily available group of Army Reserve Soldiers. The Selected Reserve is comprised of Troop Program Units (TPUs), Active Guard and Reserve (AGR) Soldiers and Individual Mobilization Augmentees (IMAs). In the event of an emergency, all members of the Selected Reserve can be mobilized.

•  Troop Program Units (TPU):
TPUs are the heart and soul of the Army Reserve. These men and women typically train on selected weekends and perform annual training. 
•  Active Guard Reserve (AGR):
AGR Soldiers serve full-time on Active Duty in units and organizations of the Army Reserve, or that directly support the Army Reserve.
•  Individual Mobilization Augmentees (IMA):
The Army Reserve's IMAs are assigned to high-level headquarters where they would serve if mobilized. Most IMAs train annually for two weeks.

Individual Ready Reserve (IRR)
Members of the Individual Ready Reserve (IRR) are trained Soldiers who may be called upon, if needed, to replace Soldiers in Active Duty and Army Reserve units. Many of the Soldiers in the IRR have recently left Active Duty and still have an Army Reserve commitment. Others have chosen to remain Active as Army Reserve Soldiers but not as a unit member or IMA.

Retired Reserve
The Retired Reserve consists of retired Soldiers from the Army (Active Army, Army Reserve and Army National Guard) who remain part of the Army Reserve family.

Civilian Workforce

The Army Reserve includes civilians working in communities across the country and around the world to provide organization, administration, training and maintenance support for Army Reserve Soldiers. Learn more about how these civilians help ensure the highest possible level of Soldier and unit readiness.

The Army Reserve includes civilians working in communities across the country and around the world. Civilians play an important role in the Army Reserve, providing continuity and expertise at every level of the organization.

Army Reserve civilians (along with Military Technicians, who work as civilian employees and also train as Army Reserve Soldiers) provide administrative support, facility management, policy analysis and program management. Civilians also ensure that the Army Reserve continues to function administratively when its Soldiers are deployed on missions across the globe.

Currently, there are more than 12,600 civilians in the Army Reserve