Cancer screening rates among Latinas are generally low, reducing the likelihood of early cancer detection in this population. This article examines the effects of a community intervention ("Fe en Acción"/Faith in Action) led by community health workers ("promotoras") on promoting breast, cervical and colorectal cancer screening among churchgoing Latinas. Sixteen churches were randomly assigned to a cancer screening or a physical activity intervention. We examined cancer knowledge, barriers to screening and self-reported mammography, clinical breast exam, Pap test, fecal occult blood test and sigmoidoscopy or colonoscopy at baseline and 12 months follow-up. Participants were 436 adult Latinas, with 16 "promotoras" conducting a cancer screening intervention at 8 out of 16 churches. The cancer screening intervention had a significant positive impact on self-reported mammography (OR = 4.64, 95% CI: 2.00-10.75) and breast exams in the last year (OR = 2.82, 95% CI: 1.41-5.57) and corresponding reductions in perceived (87.6%) barriers to breast cancer screening (P < 0.008). Cervical and colorectal cancer screening did not improve with the intervention. These findings suggest "Fe en Acción" church-based "promotoras" had a significant impact on promoting breast cancer screening among Latinas. Colon cancer screening promotion, however, remains a challenge.