Purpose: This is a retrospective review of our experience using high-dose-rate (HDR) brachytherapy boost for prostate cancer., Methods and Materials: During the study period, we recommended external beam radiotherapy (45 Gy) and HDR boost (18 Gy in three fractions) combined with hormonal therapy (HT) for 2 months before and during radiotherapy to patients with at least one of the following risk features: pretreatment prostate-specific antigen>10, Gleason score (GS)>or=7, and clinical T3 disease. Additional HT for 2 years after radiotherapy was recommended for patients with GS>7. To patients whose risk of positive nodes exceeded 15%, we recommended whole pelvic radiotherapy. We administered HDR via single implant, and all fractions were given within 24h., Results: This report is based on our initial 64 patients treated with HDR boost. The median follow-up was 50 months (range 25-68 months). The 4-year estimates of overall and disease-free survival were 98% and 92%, respectively. One patient experienced late grade 4 gastrointestinal toxicity., Conclusions: HDR brachytherapy is an effective means of delivering conformal prostate radiotherapy, and may be used with whole pelvic radiotherapy and HT.