In the decerebrate rabbit etomidate caused dose-related decreases in mean arterial pressure and preganglionic sympathetic nerve activity. There were no significant alterations in heart rate. Etomidate was found to have no effect on the baroreceptor reflex. In pithed animals the effects of etomidate were of short duration and of a lesser magnitude than in the decerebrate animal. It was concluded that the additional effects in the decerebrate rabbit were a result of depression of central cardiovascular control. It was found that etomidate was largely without effect on the cardiovascular system at normal anaesthetic doses (0.5-1 mg-kg-1). However, larger doses (2-8 mg kg-1) produced marked depression of central cardiovascular control, the myocardium and the peripheral vasculature.