Galactography is useful in the evaluation of spontaneous discharge from the nipple of a nonlactating breast. Without galactography, surgeons have relied on either masectomy or excision of the major duct system responsible for the discharge. From January 1989 to May 1996, 106 galactograms were performed with monofilament polypropylene suture guiding for duct cannulation in 105 cases. The discharge duct was identified by pre-operative galactography, followed by a selective excision of ductal-lobular unit. In all tissue specimens, the cause of the pathologic secretion was found histologically; most often, it was intraductal papilloma (42.6%). In 35.6% of the specimens, findings with a prospective significance (papillomatosis, hyperplasia, carcinoma) were discovered and further operative treatment was initiated. The color of the discharge allowed no prediction of the histological findings. The accuracy of galactography was 88.4%, 84.6%, and 77.4% in papilloma, cancer, and other benign lesions, respectively. It is better than physical examination and other tests. Galactography represents a useful test in the diagnostic workup of secretory breasts.