Following the demonstration that adjuvant arthritis in rats can be cured with total body irradiation (TBI) and allogeneic or syngeneic bone marrow, the efficacy of autologous bone marrow was investigated in the experiments reported here. Bone marrow from arthritic rats, harvested at the same time that the recipients were irradiated, and real autologous bone marrow were found to be similarly effective as bone marrow grafts from naive syngeneic donors. Sublethal TBI with lower doses was less effective, but the highest tolerated doses of 8 Gy approached the effect of 9 Gy and bone marrow rescue. In contrast, partial body irradiation of either the affected limbs, or of the whole body except the limbs, resulted in only partial and temporary regression of the arthritis.