External beam radiation therapy (EBRT) for prostate cancer is safe and effective, and dose escalation improves cancer control without increasing the risk of serious side-effects. Advanced radiation technologies can be used creatively to spare normal tissue, increase dose and dose per fraction, account for organ motion, localize and boost the tumor, and reduce overall treatment time. Proton beam therapy (PBT) is a promising but costly technology with attractive physical properties that can further spare normal tissues and avoid the low dose radiation bath of intensity-modulated radiation therapy (IMRT). Dosimetric planning and second cancer modeling studies show potential benefit to PBT over IMRT. Retrospective studies in prostate cancer are mixed, with some suggesting the potential for decreased acute bowel and urinary morbidity for protons over photons. If all forms of high dose radiation are comparably efficacious, then rigorous quality of life and economic analyses are needed to determine their true justification and appropriate use. While medicine can no longer afford expensive therapies of uncertain benefit, we must continue to invest in and promote scientific innovation and creativity and harness the potential promise of these advanced technologies and associated technical advances.