Peter Bader, MD from the University Hospital Frankfurt, Frankfurt, Germany presents the question of whether total body irradiation (TBI) can be skipped in the treatment of children. Dr Bader is also Chair of the EBMT Paediatric Disease Working Party. He describes the ongoing worldwide randomized trial led by the EBMT in which children either receive TBI or chemotherapy as a conditioning regimen. Dr Bader goes on to discuss the importance of detecting relapse and patients at high risk of relapse after allogeneic transplantation by chimerism and minimal residual disease (MRD). More novel and specific therapy options are available which can be given to high risk children to avoid relapse. Recorded at the 2016 EBMT International Transplant Course (EBMT-ITC) in Barcelona, Spain.