Breast cancer is one of the most common cancers among women in the United States (U.S. CSWG, 2009). Health care, screening behaviors (e.g., mammography) and late-stage disease detection account for significant differences in breast cancer morbidity and mortality among ethnically diverse women (ACS, 2007). The current study sought to identify variables that best predict women's breast cancer screening behaviors and to develop screening typologies for women in a large multiethnic sample (N = 15,130) from the California Health Interview Survey 2005 (CHIS, 2006). The study examined whether ethnicity (Hispanic, African American, Asian, and non-Hispanic white) moderated the relationship between emergent typologies and screening outcomes. Variables of interest addressed the following themes: health behaviors, women's health, cancer history, health insurance, health care utilization, mental health, as well as acculturation, racial discrimination, education, and socioeconomic status. Latent profile analysis (LPA: Lanza, Flaherty, & Collins, 2003) was employed to empirically derive and subsequently predict screening using each variable simultaneously to develop typologies of women. Post-hoc analyses using logistic regression were utilized to explain significant ethnicity by class interactions. Results revealed three substantive risk domains, Health, Stress, and Demographic, were significantly related to breast cancer screening. LPA revealed two classes, deemed Healthy and Health Risk, emerged significant for the Health domain. Health Risk class women engaged in more mammography screening, relative to Healthy class counterparts across all ethnic groups (ps < .001). In the Stress domain Minimal, Mild, Moderate, and Severe Stress classes emerged. Women reported more breast cancer screening in the Minimal and Mild Stress classes, comparatively to their Moderate and Severe Stress class counterparts (ps < .001). This relationship was significant in follow-up analyses for nonHispanic white women. Among the Demographic domain Minimal, Limited, Moderate, and Substantial Resource classes emerged. Women in the Minimal and Substantial Resource classes engaged in greater breast cancer screening (ps < .001) than Limited and Moderate Resource class women and this was replicated across ethnic groups. The current study portrays a rich constellation of variables that influence women's screening behaviors and underpins future targets of breast cancer prevention in typologies of ethnically diverse women within California.