This study examined the relationships among objective and subjective risk for breast cancer and mammography stages of change as defined by the Transtheoretical Model. Women who had higher objective risk of breast cancer, as defined by the Gail et al. algorithm (M. H. Gail et al., J. Natl. Cancer Inst., 81: 1879-1886, 1989), were more likely to perceive themselves at greater subjective risk for breast cancer. Among the components of objective risk, family history of breast cancer was the only significant predictor of subjective risk. Both objective and subjective risk individually predicted stages of change, such that higher objective and subjective risk were associated with an increased probability of being in a later stage of adopting mammography. However, when objective and subjective risk were included in a multivariate model, only subjective risk predicted stages of change. In additional multivariate analyses, subjective risk continued to predict mammography stages of change when "con" and "decisional balance" scores were included in separate models. These results suggest that future research may benefit from the explicit integration of personal risk perceptions with elements of the Transtheoretical Model to provide more powerful accounts of behavioral change processes.