The Young Women's Christian Association (YWCA) originally formed in England in 1855. In the United States the YWCA combined evangelism and pragmatic activism to provide for the physical, social, mental, and spiritual needs of young women living on their own. The organization strove to provide “wholesome” activities for women and girls living in cities and to develope civic-minded female leadership. In addition to Christian guidance, local YWCA braches offered residences, cafeterias, job training, daycare, exercise, crafts, camping, dances, and other services. By 1906 the U.S. YWCA had over 186,000 members. In 1907 it incorporated and established its headquarters in New York City. Today YWCA branches function fairly autonomously and respond to local needs and conditions. Currently, there are nearly 300 U.S. branches serving some 2 million women, and there are chapters in more than 122 countries.

The YWCA of Silicon Valley was organized in 1905 and incorporated in 1914. The organization struggled initially, disbanding in 1909 because of debt, but by 1914 local women were in the midst of a $75,000 fund drive to match a $25,000 donation by Maria Schofield for a YWCA building in San Jose. Julia Morgan, architect for a number of YWCA buildings on the west coast, was hired to design the building and in 1915 the cornerstone was laid on Second and San Antonio Streets in San Jose. An annex was added in 1926, and the expanded building included residences, a cafeteria, a gym and pool, and club rooms. The Morgan building was demolished in 1973 to make way for the San Antonio Plaza urban renewal project. The current YWCA facility, Villa Nueva, opened in 1993 after a $3,000,000 capital campaign matched by state, local, and federal funds. The Villa Nueva facility includes low-income housing, childcare facilities, and administrative offices.The agency was renamed the YWCA of Silicon Valley in 2004.

The YWCA pioneered services to poor and working women in the valley. The national YWCA worked to improve the conditions of girls working in factories, passing resolutions at their 1920 convention calling for an 8-hour day and the right to organize and collective bargaining. The YWCA started the Girl Reserves in 1918, a club devoted to patriotic work and charity, as well as picnics, hiking, and camping at Ayun Mapu in Big Basin and Asilomar in Pacific Grove. The Business Girls League, founded in 1930, offered vocational counseling, classes, and clubs for working women. Between 1942-1946 YWCA, the Red Cross, and the United Service Organization recruited Victory Girls to attend dances with soldiers. When Japanese Americans were interned during World War II, the YWCA accompanied single women and set up branches in the internment camps. By the 1950s the Girl Reserves had become the Y-Teens, with groups at local high schools and conferences at Asilomar and other locales. This shift reflected local youths’ interest in more social and co-educational activities. The Hi-Spot (1944-1959, re-opened briefly in 1961) was a popular teen center governed by a council of high school students with an adult advisory board. The Hi-Spot offered a snack bar, classes and discussions, sports, games, dances, and a Sunday column in the San Jose Mercury entitled “Hi-Spot News.” By the 1950s the majority of its members were Latino youth.

The YWCA also served the needs of older women in this period through programs such as “Ladies Day Out” and clubs such as the Y-Wives. While local programs had served the racially diverse population as early as the 1930s, in the 1960s the YWCA began to address the issue of racial justice more aggressively. Responding to pressure from local branches, the national YWCA passed an "Interracial Charter" in 1946. The charter mandated the active integration of women of color into programs, facilities, and governing bodies. In 1965 the national YWCA created the Office of Racial Justice, and in 1969 the first of eight Racial Justice Institutes was held in Palo Alto. In 1970, the national YWCA adopted the One Imperative: “To thrust our collective power toward the elimination of racism, wherever it exists, by any means necessary.” Locally, the YWCA established a Racial Justice Committee, which published a Directory of Black Businesses, it held race dialogues, and it developed youth programs and multicultural curriculum. In 1973 Inez Jackson became the first African American to be elected Board President of the YWCA.

The YWCA offered a number of innovative programs in this era, including the Young Mother’s Education Program (1967), which partnered with the San Jose Unified School District to keep young mothers in school; the 24-hour Rape Crisis Hotline (1973); and the Hispanic Outreach Program (1978), which offered childcare, youth programs, clubs, and citizenship and English as a Second Language courses. Rape Crisis services expanded in the 1970s, developing a speaker’s bureau and collaborating with police, the district attorney, and the county hospital to assist victims of sexual assault. In the 1980s and 1990s YWCA programming expanded to include Child Assault Prevention, Parent Education, Career Development, and two major outreach and fundraising events, a Tribute to Women in Industry (1985) and the Professional Women’s Luncheon (1991). More recent organizational activities and programs include the election of the first men to the Board of Directors (2004), Walk a Mile in Her Shoes (2003); an event at which male community leaders walk a mile in women’ shoes to raise awareness about sexual assault. The Social and Racial Justice Program (2006), an anti-bias education program, New Options, a multilingual after school program, and TechGYRLS (2007) and an after-school program that teaches girls technological and engineering skills. Fran Smith was commissioned to write the history of the YWCA of Silicon Valley. Her book, Breaking Ground: The Daring Women of the YWCA in the Santa Clara Valley 1905-2005, was published in 2005.