This study identified patient, provider, and health care system factors that influenced mammography rescreening among non-insured, racial/ethnic minority women. Data were collected using a stratified-clustered random sample survey of 1,050 women of five racial/ethnic groups (Latina, Chinese, Filipina, African American, and Caucasian) and 102 primary care clinical sites. Women received screening services through two no-cost screening programs in California. Chi-square tests were used to assess bivariate associations and multiple logistic regressions were used to compute adjusted odds ratios and 95% confidence intervals. Mammography rescreening was associated with living in the United States longer; having higher education levels, better health care access, a history of breast problems, and favorable perceptions of mammography; obtaining regular Pap screening and hormone replacement therapy; having had better communication with clinicians; and attending clinics that conducted in-reach activities. This study suggests that simply removing financial barriers is not enough to improve mammography rescreening among underserved women.