A 2-year-old boy underwent liver transplantation for fulminant hepatic failure of unknown cause. Four months later the child developed severe aplastic anemia. Allogeneic bone marrow transplantation (BMT) was performed using marrow from his 14-month-old HLA-identical sister. Severe aplastic anemia recurred 2.5 months later. After reconditioning a second BMT was performed using the same donor. Tapering of immunosuppression 2 years after BMT led to biopsy-confirmed rejection of the liver. Therapy with high-dose corticosteroids and an increase in cyclosporine A medication readily reversed rejection and a low-dose immunosuppression reflected by cyclosporine trough levels less than 50 ng/ml has been maintained since. Eight years later the boy is in excellent health with both bone marrow and liver functioning perfectly. In summary, this case demonstrates that even recurrent severe aplastic anemia after OLT can be cured by BMT, and that a transplanted liver can tolerate a double conditioning regimen without problems. Tolerance towards the liver through BMT did not develop.