CHLORPROMAZINE is the result of one of those fateful accidents which have had a profound influence on the history of medicine. Developed a decade ago, it is unlikely that at the time anyone had a presentiment of the impact this drug would have on medicine, especially psychiatry. Yet 10 yr later it can be recorded that chlorpromazine has been prescribed for an estimated 50 million patients, that it has been the subject of or mentioned in more than 10,000 scientific publications, and that most physicians in the world have had occasion to use it as either an antiemetic, a potentiator of other drugs, or a calming agent. Few medicinals have such a record. In 1952, Delay and associates1first reported the clinical use of chlorpromazine in the management of psychoses. This report was followed by worldwide clinical trials which generated an enthusiasm unparalleled in psychiatric history. Within 2