Behavioral theories developed through research with mainstream, English-speaking populations have been applied to ethnically diverse and underserved communities in the effort to eliminate disparities in early breast cancer detection. This study tests the validity of the transtheoretical model (TTM) decisional balance measure and the application of the TTM stages of change in a multiethnic, multilingual sample. A random sample of 1,463 Filipino, Latino, African American, Chinese, and White women aged 40 to 74 completed a phone survey of mammography beliefs and practices. Consistent with the TTM and independent of ethnicity, decisional balance was associated with mammography stage in all five ethnic groups when controlling for socioeconomic and other factors. In addition, having private insurance and a regular physician and being a long-time resident in the United States were positively associated with mammography maintenance. The application of the TTM for mammography is supported in a multiethnic and multilingual sample. (Contains 3 tables.)