The Medical Reserve Corps (MRC) is a network in the U.S. of community-based units initiated and established by local organizations to meet the public health needs of their communities. It is sponsored by the Office of the Assistant Secretary for Preparedness and Response (ASPR) in the US Department of Health and Human Services (HHS). The MRC consists of medical and non-medical volunteers who contribute to local health initiatives, such as activities meeting the Surgeon General's [1] priorities for public health, and supplement existing response capabilities in time of emergency. The MRC provides the structure necessary to pre-identify, credential, train, and activate medical and public health volunteers.

The Medical Reserve Corps Program (MRC PO) is the national "clearinghouse for information and guidance to help communities establish, implement, and sustain MRC units nationwide."

As of January 2020, there are 839local MRC units and 175,283 volunteers. MRC units are present in all 50 U.S. states, Washington, D.C., Guam, Palau, Puerto Rico, and the U.S. Virgin Islands.