Field observations and interviews with possessed individuals in contemporary Trinidadian society indicate that the incorporation of the local folklore and superstition is the prime prerequisite for the possession complex, but that the reaction per se is triggered by situations of unusual stress or emotional conflict. Although a consistent clinical picture of psychopathology is not apparent, the four reported case histories consistently reflect a tendency toward hysterical features, sometimes in conjunction with neurotic depression. In all cases, however, possession affords two positive advantages to the individual-direct escape from a conflict situation and diminution of guilt by projecting blame on to the intruding spirit. Mlental illness has often been attributed to supernatural powers. Although a conception of man as the supernatural battleground of eternal demonic war for the possession of his soul was most prevalent in the Middle Ages, archeological and anthropological evidence indicates that even Stone Age man had a demon-ridden cosmos and a sorcerous treatment of madness. With modification, this "evil spirit" theory has endured for centuries, and instances of demon possession are still apparent in both primitive and advanced twentieth century societies. This paper seeks to examine the psychodynamics of demon possession in contemporary Trinidadian society, and focuses on the predisposing, precipitating and cultural factors which contribute to this condition. This includes analysis of Trinidadian folk beliefs and superstitions as well as isolation of specific stress factors in individual case histories. The paper also comments on the pragmatic nature of the possession-reaction and the advantages afforded by allowing the individual to escape from unpleasant reality as well as projecting feelings of blame or guilt on to the