Eighteen patients with multiple myeloma were treated by hemibody irradiation using large single fractions, usually to a dose of 10 Gy (lower half) and 7.5 Gy (upper half). All except one patient had previously been treated by multiple courses of conventional chemotherapy with melphalan and prednisone, and were considered to be resistant to further chemotherapy. In most cases, local field irradiation had also been given for symptomatic bone pain. Of the 13 patients who had symptoms at the start of hemibody irradiation, 11 improved sufficiently for their analgesia requirement to be reduced. In eight patients, there was a significant fall in circulating immunoglobulin but no patient with Bence-Jones proteinuria had complete resolution of this biochemical abnormality. Although thrombocytopenia and neutropenia were common, only two patients required platelet transfusion and the treatment was in general extremely well tolerated. Survival following hemibody irradiation was similar to the survival reported from the use of "second-line" chemotherapy and we feel that hemibody irradiation is a more acceptable alternative for most patients.