Between 1974 and December 1985 180 bone marrow transplants were performed in Switzerland for patients with leukemia. They were performed in 4 centers (Basle 133, Zurich 28, Geneva 17, Berne 2). The overall probability of survival at 10 years for all patients is 20%. Results are better for younger patients, for patients transplanted in recent years and for patients transplanted either in the first complete remission of acute leukemia or in the chronic phase of chronic myeloid leukemia.