Emergency physicians frequently perform painful but necessary procedures on frightened children. We conducted a prospective, uncontrolled clinical trial of ketamine sedation (4 mg/kg IM) to facilitate a variety of procedures in 108 children aged 14 months to 13 years. Acceptable conditions were achieved with a single injection in 97% of the patients, and adjunctive restraint or local anesthesia was not required in 86%. Full sedation was produced within five minutes in 83%. Mean duration from injection to dischargeable recovery was 82 minutes (range, 30 to 175 minutes). One 18-month-old child vomited shortly after injection and experienced transient laryngospasm with cyanosis; intubation was not required, and there were no adverse sequelae. Airway patency and independent respirations were fully maintained in all other patients; no hemodynamic instability occurred at any time. There were no other clinically significant complications. Emesis well into the recovery phase was noted in 6% of the patients. Nightmares were not observed. Response from parents and physicians was strongly positive. Ketamine can be effectively used by emergency physicians to facilitate procedural sedation, yet equipment and expertise for advanced airway management are mandatory due to the rare occurrence of laryngospasm.