Eighty-seven patients with newly diagnosed Hodgkin's disease, pathologic stages IA, IIA, IIB and IIIA, were assigned at random to receive either extended field radiotherapy alone or that therapy followed by six cycles of MOPP (nitrogen mustard, Oncovin®, procarbazine, prednisone) chemotherapy. Patients were entered into the study from January 1970 to January 1974. Patients were followed for a median of 69 + months from the end of all treatments. Patients whose disease was less than stage IIIA had a 31 per cent relapse rate with radiotherapy alone compared to a 6 per cent relapse rate with combined modality treatment (P = 0.04). No deaths from Hodgkin's disease have occurred in patients who received combined modality therapy, whereas 24 per cent of the patients who received radiotherapy alone have died with active disease. However, three patients with stage IIIA disease who were treated with both modalities have died from other causes (myocardial infarction, adenocarcinoma of lung, acute leukemia). Combined modality therapy of patients with early Hodgkin's disease may be superior to radiotherapy alone, especially for certain subgroups of patients discussed in detail. © 1979.