Pediatric tumors still represent a formidable challenge despite the considerable therapeutical advances that have been reported for the past 30 years. This is largely related with the untowards side-effects of local therapy that are still acknowledged as the "price for cure". In this setting, Proton therapy a sophisticated radiotherapeutical modality seems to represent a real breakthrough due to its unique ability to spare close and distant normal organs compared with modern photons techniques. We summarize in this paper current clinical and dosimetrical evidences including an update of the Orsay series on 108 children.