Rocuronium is a new nondepolarizing neuromuscular blocking agent (NDNMBA) that has recently been introduced for clinical use. Its main advantage over other such agents is its rapid onset of action, which may lead to its use as the relaxant of choice when rapid intubation is required. An additional advantage is that, unlike other amino-steroidal NDNMBAs, rocuronium does not produce active metabolites. The potency of rocuronium is five times lower than that of vecuronium and its half life at its place of effect is shorter. Selectivity for the laryngeal muscle system is greater, possibly explaining the rapid onset observed. Hemodynamic stability, along with the absence of histamine release even at doses as high as 4 to 5 ED95, allow it to be used in high risk patients. Successful use has been reported in emergency surgery in patients with full stomachs, in cesarean deliveries, in cardiovascular surgery, and in liver, kidney and other transplants. Rocuronium administered in repeated doses or in continuous infusion provides adequate muscle relaxation over the required period, with predictable reversibility of effects.