An international study of 865 people with Shwachman–Diamond syndrome (SDS) has provided the clearest picture to date of the long-term blood and cancer risks associated with this rare inherited disorder. SDS, which is caused predominantly by changes in the SBDS gene, affects the bone marrow and substantially increases the risk of developing serious blood disorders, including myelodysplastic syndrome and acute myeloid leukaemia. The study found that the risk of developing a myeloid cancer increases markedly with age, reaching approximately 50% by age 50, while nearly 78% of patients experienced a major blood-related complication by this age. Outcomes were particularly poor once myeloid cancer had developed. Importantly, patients who underwent stem-cell transplantation because surveillance had identified high-risk changes before cancer developed showed encouraging outcomes, although the number of patients was small. The findings highlight the importance of lifelong specialist monitoring in SDS and suggest that identifying high-risk changes early may provide an opportunity for preventative stem-cell transplantation before leukaemia develops. The work was undertaken by the International SDS Research Consortium.