Breast cancer remains the most common malignancy in women. It is believed that the majority of breast cancers begin in the ductal epithelium originating with normal cells and progressing to atypia and finally to carcinoma. Recent advances in endoscopic technology have made visualization of the ductal epithelium possible. Ductoscopy enables one to sample the ductal epithelium and therefore identify early changes cytologically. This procedure involves cannulating a segment of the ductal system and introducing a 0.7 mm endoscopic into the duct. The ductal epithelium is then directly visualized with the images magnified 60x. Directed cytological samples are obtained using a tricut feature of the introducer and cytology brushes. An important aspect of breast endoscopy is patient selection. Presently, this procedure is used as a diagnostic tool for patients with spontaneous nipple discharge and as a risk assessment tool in high-risk patients. This video demonstrates the technique of performing mammary ductoscopy with intraductal biopsy performed as an office procedure with topical anesthesia. There are also video images of DCIS breast cancer recurrence, sclerosing papilloma and papillomatosis. A 42 year old female who underwent breast conservation and sentinel lymph node biopsy for her stage 1 breast cancer one year ago is presented. Her adjuvant treatment included chemotherapy, radiation and tamoxifen. She presented with spontaneous bloody nipple discharge. Breast endoscopy showed ductal abnormalities that were suspicious for recurrence. Cytology confirmed the diagnosis of recurrent breast cancer. Mammary ductoscopy is a potentially useful tool in the evaluation of patients with spontaneous nipple discharge and high-risk patients. Based on our experience this is a well-tolerated office procedure with minimal risk and complications. Further research is presently being conducted and is necessary to confirm these potential applications.