Objective To prospectively evaluate the ef®cacy and safety of periprostatic local anaesthesia (LA) during prostatic biopsy guided by transrectal ultrasonography (TRUS), as 20±65% of men report moderate to severe pain, and there is anecdotal and published evidence that periprostatic anaesthesia improves patients' tolerance. Patients and methods In all, 157 patients were prospectively recruited and sequentially randomized to receive either LA or no anaesthesia. Sextant biopsies were taken in all men but some had more than six biopsies. All were asked to complete questionnaires immediately after TRUS-guided biopsy and for the subsequent week, giving pain scores and recording any morbidity, including symptoms of infection; analgesic use was also surveyed. Results Patients given LA had signi®cantly lower pain scores at the time of biopsy than those given no anaesthesia, with median (SD) pain scores of 1.53 (0.7) and 1.95 (0.65) (P<0.001), respectively. In addition, there was a trend towards less analgesic use by those given LA, although this was not statistically signi®cant. There was no difference in the amount of haematuria, haematochezia or haematospermia, or infection rate, between the groups. The additional cost and time of the procedure was minimal (£3.00 and 3 min/per patient, respectively). Conclusion Periprostatic LA in®ltration is a quick and simple procedure which signi®cantly improves immediate pain with no added morbidity; we strongly advocate its use to improve patient tolerance of TRUS-guided prostate biopsy.