This randomized double blind study compared the haemodynamic response and recovery profile of the new potent I.V. anathestic remifentanil which is an ultrashort acting opioid versus alfentanil. 100 patients scheduled for labaroscopic cholecystectomy received either remifentanil 0.5 g/Kg/min combined with propofol. A smaller proportion of remifentanil patients had less responses to intraoperative stress than alfentanil. Remifentanil patients had a shorter time to respiration, extubution, and response to verbal commands.