Eighteen patients with pathologic Stage (PS) III1A Hodgkin's disease were treated with mantle and para-aortic field radiation therapy alone between 1973 and 1988. The median follow-up time is 84 months (range 20-174 months). The 5-year survival and relapse-free survival rates are 76 and 82%. Six patients had extensive splenic involvement or bulky mediastinal adenopathy, and three have relapsed and are dead of disease. Of the other 12 patients, only one has had recurrence of disease and died. Patients with PS III1A Hodgkin's disease are good candidates for mantle and para-aortic radiation therapy only, provided that they do not have extensive splenic involvement or large mediastinal adenopathy.