Between 1985 and 1987 quadrantectomy plus external radiotherapy and lumpectomy plus external and interstitial radiotherapy were compared in a randomized trial of patients with small carcinomas of the breast. Quadrantectomy involves excision of 2-3 cm of normal tissue around the tumour plus the removal of a sufficiently large portion of overlying skin and underlying fascia whilst lumpectomy removes only the tumour mass with a narrow margin of normal tissue. Patients in both groups also received total axillary dissection. 705 cases were evaluable, 360 quadrantectomies and 345 lumpectomies. No differences in distant metastases and survival were observed in the two groups. However, lumpectomy patients had a much higher frequency of local recurrences (7.0 vs. 2.2%). Since a local recurrence needs a second operation and creates severe psychological distress to the patient, conservative surgical procedures should include generous excision of normal tissue around the primary carcinoma plus intensive postoperative radiotherapy.