1982.--Various indolealkylamine and phenalkylamine derivatives are hallucinogenic in man and/or are behaviorally active in animals. This overview is divided into two parts. The first part attempts to bring together information concerning the activity of indolealkylamines (i.e., tryptamines, a-methyltryptamines, N,N-dimethyltryptamines, N-alkyltryptamines, lysergic acid derivatives and /3-carbolines) and phenalkylamines (i.e., phenethylamines, phenylisopropylamines) along with major key references, and with emphasis on those agents not recently reviewed. The latter portion of this overview describes some of the work being conducted in our laboratories in an effort to elucidate the role of the neurotransmitter serotonin in the mechanism of action of various indolealkylamine and phenalkylamine hallucinogens. Indoleatkylamine hallucinogens Phenalkylamine hallucinogens Discriminativestimulus properties Phenylisopropylamines Phenethylamines Tryptamine derivatives LSD /3-Carbolines a-Alkyltryptamines Serotonin