In patients with acute myeloid leukaemia (AML) in first complete remission, reduced-intensity conditioning (RIC) regimens have been developed to minimize toxicity after allogeneic stem cell transplantation. Now, a randomized phase III trial that compared standard conditioning with RIC, showed that nonrelapse mortality, disease-free survival and overall survival were comparable, but grade 3 or 4 oral mucositis was lower with the RIC regimen, indicating that this is the preferred option.