Thanks to improved surgical techniques, postoperative management and immunosuppressive therapies, an increasing number of children benefit from renal, hepatic, cardiac and pulmonary transplantation. Infection is a significant cause of mortality and morbidity in these patients, particularly due to vaccine-preventable diseases. Vaccination is one of the effective means of reducing infection-related mortality in these particularly vulnerable children. It is mostly well-tolerated, but all the more effective as it is performed early before transplantation, at best during a dedicated consultation, according to a vaccine scheme adapted to the immunocompromised child. In the almost constant absence of clinical efficacy data in populations of immunocompromised individuals, vaccine efficacy is most often indirectly estimated by immunogenicity, using protective correlates obtained by extrapolation in immunocompetent individuals.