The American Board of Obstetrics and Gynecology has recognized the special role of the obstetrician/gynecologist in the diagnosis and treatment of breast disease and indicated in 1985 that it would require a knowledge of breast disease in its certification process. It was also recommended that the obstetrician/gynecologist provide adequate information concerning screening and perform simple diagnostic studies including aspiration of cysts, fine-needle aspiration, and appropriate follow-up studies for patients treated for breast cancer. Because open biopsy often becomes part of the treatment for breast cancer, the Board stopped short of recommending that every obstetrician/gynecologist perform this procedure. The American College of Obstetricians and Gynecologists also has increased its efforts to more clearly define the role of the obstetrician/gynecologist in the diagnosis and treatment of breast disease. Questions have been raised concerning the lack of national standards to evaluate training in the diagnosis of breast disease surgery, and the College has convened a number of workshops to address these issues. This review discusses the issues raised both by the Board and the College. Diagnostic studies including simple procedures such as aspiration of cysts, fine-needle aspiration, and open biopsy are discussed. The role of the obstetrician/gynecologist in the screening examination is emphasized.