Objectives: Sentinel lymph node biopsy (SLNB) is widely used for staging breast cancer. SLNB accurately determines axillary lymph node status with a low false negative rate. There remains concern that omitting axillary dissection may lead to recurrence in the axilla, and impact long term survival. The purpose of this study was to determine the frequency of axillary lymph node recurrence in patients who had a negative sentinel lymph node and did not undergo axillary node dissection. Methods: Data was collected on all patients who had negative SLNB at Roswell Park Cancer Institute between July 1997 and June 2002. Demographics, type of operation, postoperative systemic, and radiation therapy, co-morbidity score, hormone receptor status, and the pathologic features of the tumor were abstracted for each patient. For each woman with recurrence, the dates of recurrence, the site(s) of recurrence, and the treatment for recurrence were recorded. Results: With a median follow-up of 33 months, 15 of 335 (4.5%) women who had negative SLNBs and who did not undergo completion axillary dissection developed a cancer recurrence. Only two patients (0.6%) had an axillary recurrence. Conclusions: The rate of axillary recurrence following a negative sentinel node biopsy is the same or less than axillary lymph node dissection (ALND) alone. Concerns that omitting completion axillary dissection following a negative SLNB will increase the rate of axillary recurrence appear unfounded.