With approximately 70 active members, SDMRT responds to calls at any time to search for and rescue missing, injured or stranded persons in San Diego County and, through mutual-aid requests, in other counties within the state of California.

[3] It routinely works with the San Diego Sheriff's Office Search and Rescue Bureau and San Diego's Aerial Support to Regional Enforcement Agencies (ASTREA) on operations within the county.

On operations outside of San Diego County, SDMRT works under the particular law enforcement agency for the region in question.

In February 1967, two Claremont College students set out to climb the 10,154 foot tall Picacho del Diablo, the highest mountain in Baja California.

After a week-long search by Los Angeles-area mountain rescue teams the couple was found severely debilitated, near death, and were rescued from the upper canyons of the mountain.