Proton beam therapy (PT) offers improved sparing of normal tissue, thus potentially reducing the risk for treatment related late sequelae and induction of secondary cancer. In addition, it can be an instrument for intensification of local therapy ("dose escalation") for disease currently not sufficiently controlled. Up to now, more than 70 000 patients have been treated with PT worldwide. In particular, tumors of the ocular fundus, the base of skull and prostate were targeted. In recent years an increasing number of children got treated, predominantly when suffering from sarcomas or brain tumors. In Europe, treatment was applied so far mainly in Switzerland (PSI) or France (Orsay). However, availability of particle therapy is about to increase considerably within the next years. The German Working Group of paediatric radiation oncology APRO=Arbeitsgemeinschaft für Pädiatrische Radioonkologie) is currently trying to embed PT in the multidisciplinary concepts of the GPOH, and PT experts are appointed for each relevant study. In addition, prospective documentation of the applied PT is to be performed according to the RISK protocol. Still, it is mandatory to reach out for the integration of PT into our cooperative network and the multidisciplinary trials. Best practice solutions have to be established in order to provide high quality and transparency of any applied particle therapy.