A double-blind and randomized study design was used to investigate 100 healthy children, aged 1–5 years. Intubating conditions and cardiovascular changes duraning deep halothane anaesthesia, defined as an endtidal concentration of 2%, were compared with those changes during 1% halothane and suxamethonium relaxation. Intubating conditions were graded according to the ease of laryngoscopy, vocal cord position, coughing and jaw relaxation. In each group 96% of the children demonstrated acceptable intubating conditions. Jaw relaxation was worse in the 1% halothane/-suxamethonium group (P < 0.01). When anaesthesia with 2% or 1% halothane was compared there was a more pronounced decrease in systolic blood pressure (18 vs. 8%, (P < 0.001). Junctional rhythm occured more frequently during deep halothane anaesthesia (46 vs.18%, (P < 0.01). Intravenously (i.v.) administered atropine attenuated blood pressure depression significantly and reinstituted sinus rhythm in most cases.