Radioactive implants have been used extensively for treatment of early stage prostate cancer. In general, their use has been associated with fewer side effects than surgery or external beam irradiation. Local control, for the most part, has been comparable to that achieved with the other modalities. Lower tumor control rates in some early series probably were related to inaccurate or inconsistent placement of radioactive pellets, since the older procedures were subject to substantial operator error. Newer transperineal techniques, guided by transrectal ultrasound or CT scanning, have provided increased accuracy of seed placement. Early results with the newer techniques are promising.