Three patients who received antithymocyte globulin therapy for severe aplastic anemia due to gold therapy are described. In 2 patients the hemoglobin, white blood cell count and neutrophils were normal and platelet counts exceeded 100 X 10(9)/1 more than 2 years after treatment. The 3rd patient did not respond to antithymocyte globulin or to cyclosporine therapy; subsequent allogeneic bone marrow transplantation resulted in satisfactory engraftment at 12 months. In all 3 patients the arthritis was improved after the episode of marrow aplasia and its treatment. Including these 3 patients, 12 reported patients with severe aplastic anemia due to gold have now been treated with antithymocyte globulin; 8 have shown significant improvement. These results are better than those reported for any other treatment. Antithymocyte globulin may be optimal initial treatment for this serious disorder.