Five children with sickle cell anaemia underwent bone marrow transplantation (BMT) for severe clinical disease. The conditioning regimen for BMT was in busulfan plus cyclophosphamide. The allograft contained more than 5 x 10(8) nucleated cells per kg recipient. Prophylaxis of GVHD consisted of methotrexate and cyclosporin A. Therapy was well tolerated. Duration of neutropenia (less than 0.5 x 10(9)/l) was short (14-25 d). Platelet recovery (greater than 50 x 10(9)/l) occurred between day 12 and 45. The patients have been followed up for 8-28 months. No major infections occurred and long-term BMT-related toxicity was limited to mild, chronic GVHD in one patient. Mean haemoglobin levels remained above 10 g/dl. Haemoglobin electrophoresis showed AS patterns in all grafted patients--all marrow donors having sickle cell trait. From our preliminary data, we conclude that BMT or sickle cell anaemia is curative, well tolerated and should be proposed for suitable patients.