The treatment of early (stage I and II) breast cancer over the past 10 years has shown a trend towards conservative use of surgery. The role of mastectomy in achieving local-regional control has been challenged by procedures that preserve the breast, in which tumor excision and axillary node dissection are followed by breast irradiation. Data from retrospective studies as well as prospective randomized trials have shown that in selected patients conservative surgery and radiation achieve results comparable to those of mastectomy in terms of 10-year survival and local-regional recurrence. Studies have shown that conservative surgery, radiation, and adjuvant chemotherapy can be combined effectively in patients at high risk for systemic disease. Although the optimal treatment of early breast cancer remains controversial, the non-mastectomy approach represents major progress.