A double-blinded, placebo-controlled study compared the outcomes of intranasal ketamine premedication with placebo in outpatients. Forty paediatric outpatients were assigned randomly in a prospective fashion to one of two separate study groups of equal size (20 patients per group). A placebo group received 2 ml of intranasal saline, 1 ml per naris. The study group received intranasal ketamine, 3 mg.kg-1, diluted to 2 ml with saline, 1 ml per naris. Using a cooperation index, a play therapist scored resistance to nasal instillation, separation of the child from parents at ten min, and acceptance of anaesthesia monitors and face mask at 15 min. Differences in age, weight, episodes of vomiting, recovery and discharge times among the two groups were not significant. Intranasal ketamine, 3 mg.kg-1, was associated with a significantly better (P = 0.013) cooperation index than intranasal placebo. Intranasal ketamine, permitted pleasant and rapid separation of children from their parents, cooperative acceptance of monitoring and of mask inhalation induction, and did not cause prolonged postanaesthetic recovery or delayed discharge home.