In 1998, a Mexican American woman named Estela Ruiz began seeing visions of the Virgin Mary in south Phoenix. The apparitions and messages spurred the creation of Marys Ministries, a Catholic evangelizing group, and its sister organization, ESPIRITU, which focuses on community-based initiatives and social justice for Latinos/as. Based on ten years of participant observation and in-depth interviews, The Virgin of El Barrio traces the spiritual transformation of Ruiz, the development of the community that has sprung up around her, and the international expansion of their message. Their organizations blend popular and official Catholicism as well as evangelical Protestant styles of praise and worship, shedding light on Catholic responses to the tensions between popular and official piety and the needs of Mexican Americans.