Local failure and related complications after definitive treatment of carcinoma of the prostate by irradiation or surgery. The authors review their institution's experience with the failure of definitive treatment to achieve local tumor control and with the distant dissemination and local morbidity associated with such failure. The causes of local failure are various: incomplete resection, implantation of spilled cells, and, possibly, selective implantation of circulating tumor cells in traumatized tissues after surgery and totally or partially resistant cells, new tumors, or radiologic misses after radiation. Treatment of local failure may be prophylactic or therapeutic and differs depending on the stage of the disease. Failure to control the tumor locally in the presence of distant metastases does not alter the length of survival, but it can profoundly affect the quality of survival. 