<p>Embryonal tumors are treated with multimodal approaches in clinical trials or according to guidelines. Radiation therapy plays a&#xa0;central role in achieving local control but is also highly demanding due to the typically very young patients. The high risk of relevant—potentially severe—late adverse events must be carefully considered when tailoring the treatment strategy. Therefore, treatment strategies are always risk adapted based on clinical, molecular, and histological markers. In particular, tumor type, tumor site, extent of disease, and pattern of relapse are key factors impacting on the treatment strategy with regard to treatment volume, radiotherapy dose, and the timing of delivery. Given the vulnerability of pediatric patients, highly conformal RT techniques such as proton therapy are increasingly used to best spare the surrounding normal tissue. As late effects of radiation therapy may only occur decades after treatment, children should undergo lifelong follow-up care to enable timely intervention.</p>