Collection includes materials related southern California tourism, the Mission Revival movement, peace movement (1st half 20th century, citrus industry, and materials related to specific collections,including fine art, statuary, bells, crosses, dolls, aviation, Native American basketry, and Asian arts.

Mount Saint Mary's University was founded by the Sisters of St. Joseph of Carondelet in 1925 as the first Catholic women's college west of the Mississippi. It comprises two historic sites, the Chalon Campus high above Brentwood (1930), and the Doheny Campus, which occupies the former estate of Edward and Estelle Doheny, including the Doheny Mansion at 8 Chester Place (1899).

The Museum Archives documents the history of the Los Angeles County Museum from its founding in 1910 to the present. The collection includes photographs, departmental papers, research papers, ephemera, publication, architectural plans, newspaper clippings and original artwork.