Autologous transplantation of lymphocyte-depleted peripheral blood stem cells (PBSC) has been proposed for treatment of patients with severe autoimmune disease. However, several patients have been reported to achieve only transient remissions. We report on a child with thalassaemia intermedia and immune-mediated haemolytic anaemia, given an autologous lymphocyte-depleted PBSC transplant, who relapsed 7 weeks after transplant. A complete remission, lasting 18 months to date, was obtained with allogeneic bone marrow transplantation (BMT) from an HLA-matched unrelated donor. This experience indicates that, in selected cases, allogeneic BMT may be the treatment of choice for life-threatening autoimmune disease. A graft-versus-autoimmunity effect may favour the eradication of the recipient autoaggressive lymphocytes.