Background. The results of pediatric renal transplantation have improved markedly in the last decade. However, a number of relevant clinical problems remain, such as organ damage caused by chronic rejection, long-term toxicity of immunosuppressive therapy, difficulty in developing tolerance-inducing protocols, secondary cardiovascular comorbidity, post-transplantation lymphoproliferative disease, suboptimal longitudinal growth, quality of life, adherence to immunosuppressive medication, and structured transition programs to adult care. These unmet clinical needs require intense collaborative and interdisciplinary clinical research. We recently founded the Cooperative European Paediatric Renal TransplAnt INitiative (CERTAIN; www.certain-registry.eu) as a research network and platform built on a novel, web-based registry.