Researchers in the JHU School of Engineering have developed a robotic needle positioning device which will allow greater flexibility in choosing needle positions for prostate brachytherapy. The device consists of a motor attached to a needle guidance hole. The entire apparatus attaches to the ultrasound 'stepper' device similar to the standard transperineal template. For each needle position, the motor moves to the predetermined location and the physician places the needle through the hole. Visual verification of acceptable needle position is performed by viewing the needle on the real-time ultrasound. A secondary means of verification will be the use of an Optical Tracking device, which will verify needle orientation and position prior to insertion. Rather than having the probe positioned at the desired endpoint of the needle insertion within the prostate, the ultrasound unit will be mechanically coupled with the needle (via the optical tracking system) as it is being inserted, such that the needle tip will be continuously visualized as it is progressing into the prostate.