This study evaluated a mail and telephone intervention to improve breast health behaviors while maintaining quality of life. Women recruited from the general public were randomized to a stepped-intensity intervention consisting of mailings, telephone calls, and counseling (if requested or appropriate given a woman's genetic risk for breast cancer) or to a delayed treatment control group. Outcomes (mammography screening and quality of life) were measured at baseline in a telephone survey and again at a 12-month follow-up period. Women in the intervention group significantly increased screening mammography uptake by 12% and quality of life by 5.3 scale points compared to control participants. Changes in knowledge of breast cancer, genetic testing, and cancer worry all significantly predicted intervention changes. This successful intervention can help women make better breast health choices without causing increased worry. (Contains 3 tables.)