Allogeneic bone marrow transplantation (BMT) is an effective therapy for Fanconi's anemia (FA). However, mortality and transplant-related complications are usually high due to increased sensitivity to the alkylating agents and radiation commonly used for pre-transplant conditioning. Fludarabine monophosphate is a purine analogue that has been proven effective as a conditioning agent for chronic lymphocytic leukemia patients. We report a child with FA in leukemic transformation with thrombocytopenia and 20% myeloblasts who underwent successful BMT following conditioning with fludarabine/ATG/cyclophosphamide. The regimen was well tolerated, no transplant-related complications were observed, and engraftment was rapid. The child is currently 10 months post-BMT, in excellent clinical condition with a normal blood count, 100% chimerism and no sign of graft-versus-host disease (GVHD). We suggest that this fludarabine-based regimen may be effective in the conditioning of standard, as well as transforming, FA patients for BMT.