Radiotherapy is needed in the multidisciplinary management of cancer in children to improve local control, overall survival and symptom management; however, it is known that radiotherapy is associated with potential toxicities.For patients with a good long term prognosis, efforts to minimize late effects is critical and technological advances have provided opportunities improve our ability to deliver therapeutic radiation.Proton therapy is a powerful tool to improve radiotherapy delivery in an effort to decrease late effects while maintaining tumor control.There is a consistent reduction in overall radiation dose to the the patient in particular within the low and intermediate dose volumes.Children are most likely to benefit from an reduction in volume of irradiated tissue.Thousands of pediatric patients have now been treated with proton therapy and clinical evidence is now increasing to support the theoretical benefits that have been proposed through dosimetric studies.Proton therapy, however, it is not needed for all children requiring radiotherapy for management of their cancer.The patient's medical history, tumor radiosensitivity, tumor volume geometry, normal tissue anatomy, and treatment options should all be considered when considering radiation treatment modalities.In this session, we will review situations where proton therapy is not necessary, or maybe associated with higher uncertainties and risk.