A long-term study of the major urologic complications following radium and x-ray therapy in 369 cases of carcinoma of the cervix, treated between 1939 and 1955, has been made. The radiation technique employed during this period was a short-term intensive radiation exposure method. The mean time of onset of the major urologic complications following treatment was similar whether due to cancer or to radiation, being 12.1 and 12.3 months, respectively. Seventeen (4.6 per cent) were noted to have major urologic complications on admission due to cancer. An additional 17 patients developed major urologic complications due to cancer after treatment. The mean survival time of the latter series was 17.4 months, with 10 patients surviving less than one year. Only 10 (2.7 per cent) patients developed major urologic complications due to radiation therapy. Of this small group, 7 lived for a mean survival time of 4.5 years, while the 3 remaining were still alive at 10, 17, and 25 years, respectively. © 1968.