From 1980 to 1989, 70 women with postmastectomy local–regional recurrent breast cancer and no clinical or radiographic evidence of distant metastasis were treated with radiotherapy with or without systemic therapy. The interval from mastectomy to local–regional recurrence ranged from 5 to 240 months (median, 34 months). The chest wall alone was involved in 37 patients, the supraclavicular area in 12 patients, the internal mammary node area in 3 patients, the infraclavicular area in 2, and the axilla in 1. Fifteen patients had multiple areas of involvement. The complete response rate was 87%. Further local–regional recurrence developed in at least 21 patients, and distant metastasis developed in at least 41 patients. Twenty-five patients (36%) survived at least 5 years and 15 patients (21%) survived at least 10 years. An initial negative node status and long disease-free interval from mastectomy to recurrence were associated with an improved postrecurrence survival. Patients with local–regional recurrence postmastectomy who do not have clinical or radiographic evidence of distant metastasis should be treated aggressively with radiotherapy with or without systemic therapy. Distant metastasis will develop in most such patients, but the majority will remain free of further local–regional recurrence.