Employer Support of the Guard and Reserve (ESGR) is a Department of Defense (DoD) organization. It is a staff group within the Office of the Assistant Secretary of Defense for Reserve Affairs (OASD/RA), which is in itself a part of the Office of the Secretary of Defense (OSD).

The nation's Reserve components (referring to the total of all National Guard members and Reserve forces from all branches of the military) comprise approximately 48 percent of our total available military manpower. The current National Defense Strategy indicates that the National Guard and Reserve will be full partners in the fully integrated Total Force. Our Reserve forces will spend more time away from the workplace defending the nation, supporting a demanding operations tempo and training to maintain their mission readiness.

In this environment, civilian employers play a critical role in the defense of the nation by complying with existing employment laws protecting the rights of workers who serve in the Reserve component.

ESGR was established in 1972 to promote cooperation and understanding between Reserve component members and their civilian employers and to assist in the resolution of conflicts arising from an employee's military commitment. It is the lead DoD organization for this mission under DoD Directive 1250.1.