Twenty-five patients with haematologic malignancies received total body irradiation (TBI) as part of their conditioning regimen prior to autologous bone marrow transplantation (ABMT). TBI was delivered with an 18 MeV photon beam through AP-PA ports; the total dose was 13.2 Gy/8 fractions over 4 days; shields were used to limit the total dose to the lung to 8-10 Gy. Five relapses were observed; among 14 patients with ALL or advanced lymphoblastic lymphoma, 10 patients are currently alive and free of disease. Acute and late morbidity of TBI were low.