During the past 10 years, some 15 publications have appeared in the English literature on the definitive radiotherapy of prostatic cancer. The long-term followup required for rational assessment of the treatment of prostatic cancer is not yet available for most of these studies. However, in the Stanford series, the direct disease-free survival at 5 years for patients with disease localized to the prostate is 70%; at 10 years, 42%. The direct disease-free survival at 5 years for patients with extracapsular extension in 36%, and at 10 years, 29%. Recently, mapping of potential lymph node metastases has been studies by several authors.Early results of extended-field irradiation required for regional treatment are presented.