This procedure begins by placing the patient in the dorsal lithotomy position. The transrectal ultrasound probe is positioned in the rectum. The prostate volume is calculated using the planimetry program. The amount of radioactivity to be implanted is deter-mined from a volume/activity look-up table. Using the largest trans-verse image of the prostate, needles are inserted into the periphery of the prostate via a transperineal template. Needles are inserted 1 cm apart. A Mick radioactive seed applicator is attached to the needle. Using longitudinal imaging, the needle is visualized and moved through the base of the gland to the apex, dropping seeds at set intervals. This process is repeated for each peripheral needle. Approximately 65-75% of the total activity is placed in the periphery of the gland. Once the periphery has been implanted, needles are placed into the interior of the gland 1 cm from each other and the urethra and the needle implant procedure is repeated. 25-35% of the activity is implanted in the interior.