Objective.\p=m-\Previousreports have demonstrated that physician counseling can improve rates of breast-feeding initiation and duration but suggest that physicians are ill-prepared for this role. It is unclear whether residency training for pediatricians, obstetrician/gynecologists, and family physicians provides the knowledge and skills necessary for effective breast-feeding promotion. Design.\p=m-\Survey. Participants.\p=m-\Anational random sample of 3115 residents and 1920 practic- ing physicians in pediatrics, obstetrics/gynecology, and family medicine. Outcomes.\p=m-\Assessmentof breast-feeding knowledge, attitudes, training, and experience. Results.\p=m-\Overallresponse rate was 68%. All groups demonstrated significant deficits in knowledge of breast-feeding benefits and clinical management; for ex- ample, less than 50% of residents chose appropriate clinical management for a breast-fed jaundiced infant or a breast abscess. Practicing physicians performed slightly better, but still more than 30% chose incorrect advice for mothers with low milk supply. Residents reported that their breast-feeding instruction consisted mainly of didactic lecture, not patient experience. Only 55% of senior residents re- called even one instance of precepting related to breast-feeding, and less than 20% had demonstrated breast-feeding techniques at least five times during residency. Regarding preparation for breast-feeding counseling, more than 50% of all practic- ing physicians rated their residency training as inadequate. Overall, physician in- volvement in breast-feeding promotion was endorsed by 90% of respondents, yet only half rated themselves as effective in counseling breast-feeding patients. The greatest predictor of physician self-confidence was previous personal or spousal breast-feeding experience. Conclusions.\p=m-\Inthis national sample of residents and practicing physicians in three specialties, physicians were ill-prepared to counsel breast-feeding mothers. Deliberate efforts must be made to incorporate clinically based breast-feeding training into residency programs and continuing education workshops to better prepare physicians for their role in breast-feeding promotion. (JAMA. 1995;273:472-476)