Research Report Series. 8 pages. March 2001.Outlines the mechanisms by which hallucinogens work and details their effects and their dangers. Includes review of such drugs as LSD, PCP, and ketamine. Topics: Letter from the Director; What are hallucinogens?; What are dissociative drugs?; Why do people take hallucinogens?; What are the facts about dissociative drugs?; Where can I get more scientific information on hallucinogens and dissociative drugs?; Glossary and References.