Prilocaine has become the agent of choice for Bier's block (or intravenous regional anaesthesia--IVRA), since 1983 when the product licence of bupivacaine was withdrawn for this purpose owing to fatal or serious complications. No serious complications have been documented in the literature relating to prilocaine in IVRA and we have conducted a survey within the U.K. which indicates that about 45,000 Bier's blocks have been carried out with prilocaine without convulsion, arrhythmia or fatality. This includes cases of accidental cuff deflation or even failure to inflate the cuff, resulting in bolus doses to the circulation. Prilocaine has now been in use since 1964 and the Committee for Safety of Medicines has no deaths on record over a 25-year period. (This includes other types of regional anaesthesia). We suggest that intravenous regional anaesthesia using prilocaine is a safe technique. It is highly unlikely that fatalities will occur, provided present guidelines are adhered to. We can find no reason to limit its use to trained anaesthetists only, but would recommend that a strict protocol is adhered to.