Emmy Lou Packard (1914–1998) was a California painter, printmaker, muralist and activist whose art reflected a lifelong commitment to social justice, workers’ rights, racial equality and environmental conservation. Born in California, Packard spent part of her childhood in Mexico, where she met Diego Rivera and began receiving his artistic guidance at age 12. She later earned a B.A. from the University of California, Berkeley, in 1936 and studied fresco and sculpture at the California School of Fine Arts. In 1940, Packard became Rivera’s principal assistant on his monumental Pan American Unity mural in San Francisco and developed close friendships with Rivera and Frida Kahlo. During World War II, she worked at the Kaiser shipyards in Richmond, creating illustrations that advocated racial integration, women’s participation in the workforce and workers’ rights. Packard later became known for bold linocuts celebrating workers, children, nature, peace and cultural diversity. She believed printmaking could make original art accessible to ordinary people. Later in life, Packard mentored younger Bay Area artists and helped connect Rivera’s mural tradition with the emerging community mural movements of San Francisco’s Mission District.