In acute leukaemias there was a stable plateau in the survival curve at 45% after two years if grafted in first complete remission (n = 20) but only 13% of the patients are disease-free alive if grafted in a more advanced stage of the disease (n = 8). In 16 patients transplanted for chronic myeloid leukaemia the overall survival is 40%, in cases with graft-versus-host disease (GVHD) prevention by cyclosporine survival rate could be improved. Only 8 patients with severe aplastic anaemia, partially in low performance status were able to be transplanted; three died of infections, another by acute GVHD. The fatal complications in our study characterize the international well-known major problems in BMT: GVHD, interstitial pneumonitis, infections, graft failure in aplastic anaemia and recurrence of leukaemia, especially in more advanced leukaemia stage.