Chloral hydrate is an oral sedative commonly used in pediatric dentistry when providing extensive treatment in the young child. This article reports the results of a clinical trial using an orally administered dose of chloral hydrate at 75 mg/kg of body weight plus nitrous oxide and oxygen. A method for administering the drug that minimizes initial drug expectoration and vomiting is also presented. Because a reliable method for delivery of chloral hydrate is essential in a study of the ideal effective dose, the authors describe a technique that makes this portion of the treatment process as pleasant as possible by associating the drug with a product known to be pleasing to most children of this age group. The results of the clinical trial of 50 patients revealed that 29 children (58%) slept through the entire procedure and 14 (28%) of the children presented only mild resistance either during anesthesia and/or treatment. If some mild resistance is acceptable to the practitioner then there was an approximately 85% success rate. The authors concluded that chloral hydrate used at a 75 mg/kg dose and supplemented by nitrous oxide/oxygen is a safe and reliably effective sedative for the preschool child.