Low Dose Rate (LDR) Brachytherapy involves insertion of tiny permanent radioactive Iodine( I -125) seeds (the seed is about the size of a grain) into the prostate gland. The radioactive iodine gives off low energy radiation that is absorbed almost entirely within the prostate itself. The implant is tailored to the shape and size of your prostate and typically 90 to 120 seeds are used. The seeds deliver a field of radiation at high doses which is largely limited to the prostate. This field of radiation is capable of killing the prostate cancer cells. Typically this is done under a general or spinal anaesthetic and can all be done in one setting. The procedure takes about 2-3 hours to complete and the patient can be discharged home on the same day or the following day. Seed implantation requires no surgical incision and offers men a short recovery time.The implanted seeds are small enough that they will not be felt by the patient.The radioactive iodine “decays” over several months. The amount of radioactivity decreases by 50% every 60 days.Compared to EBRT where the patient has to make daily visits over a period of 6 to 7 weeks, brachytherapy patients do not have to make multiple visits to the radiotherapy unit for treatment. This makes treatment accessible and convenient for many patients. Most patients are able to tolerate the brachytherapy procedure very well. The risks of serious adverse side effects are low. Patients may have irritative voiding symptoms which eventually settle. However there is a low risk of urethral stricture down the track. The risk of impotence is lower than a radical prostatectomy. Brachytherapy is an effective treatment option for patients who have a PSA <10 mcg/l, non palpable disease, low volume and intermediate Gleason grade (Gleason 3+3=6) prostate cancer and in a prostate gland that is <50 cc in volume.