Methaqualone is considered a sedative hypnotic drug with a pattern of pharmacological effects similar to those of barbiturates such as pentobarbital. It does have chemical similarities to the barbiturates but was, in fact, synthesized as part of an Indian program looking for antimalarial drugs (Brown and Goenechea, 1973). Methaqualone was selected for the focus of this study five years ago, because of its popularity as a euphoriant among casual recreational drug users in the Boston area. Methaqualone, instead of a barbiturate hypnotic, was therefore used to test our proposed methodology for the assessment of the abuse liability of sedative drugs. As one reviews the history of the clinical use and illicit abuse of methaqualone, it appears particularly unfortunate that a study of this sort was neither completed nor available to our Food and Drug Administration (FDA) and Drug Enforcement Agency (DEA) in 1965. It was at this time that the drug was approved for prescription use and placed in Schedule V, a schedule which essentially places no restrictions on the clinical use of a prescription drug (Falco, 1976). This paper will both review the development of methaqualone and present an experimental methodology for assessing its abuse liability under seminaturalistic conditions.