A better understanding of factors influencing retention in breast cancer risk education and prevention programs can improve the design and effectiveness of such programs. Such information may also be useful to researchers seeking to maximize full retention in research trials involving low risk and low perceived benefit by the participants. These data are from a population-based study of 481 women from the Seattle, Washington, area, with diverse levels of breast cancer risk. This study sought to describe motivations for retention, to relate motivation variables to demographic characteristics, and to evaluate predictors of retention. Increasing age predicted study assessment completion, and both cancer worry and White ethnicity predicted intervention retention. (Contains 5 tables.)