Fifty-eight laparotomy-staged I and II patients with upper torso presentations of Hodgkin's disease and 8 patients with lymphangiogram-staged lower torso disease were treated with radiotherapy alone or with 2 cycles of MOPP and radiotherapy. Patients with upper torso disease with either no mediastinal or only small mediastinal disease without hilar involvement and with no "B" symptoms were treated with mantle radiotherapy alone. Patients with large mediastinal masses or hilar disease were treated with 2 cycles of MOPP followed by definitive mantle irradiation and low dose lung irradiation. Those for whom "B" symptoms were the only adverse prognostic feature received 2 cycles of MOPP and mantle radiotherapy. Patients with lower torso disease were treated with radiotherapy alone if the disease was limited to the pelvis. Those with more extensive disease received 2 cycles of MOPP prior to radiotherapy. The 4-year survival for all 66 patients was 97%. The corresponding disease-free and freedom from second relapse figures were 77% and 92%. Survival for the patients with unfavorable presentations who received 2 cycles of MOPP and radiotherapy was 100%. It was 92% for the group with favorable presentations who were treated with radiotherapy only.