Ten Years After"" is the name of a rock group, and would be an apposite subtitle for this detailed survey of the rise and fall of psychedelia. The authors, well known Harvard experts who have collaborated on previous works on psychoactive drugs, comment extensively on the phenomena of the Fifties and Sixties: the flower children, Leary and Alpert, Ginsberg and Burroughs, rock music, the Vietnam War, Charles Manson. . . . They conclude that while there was a superficial unity to the counterculture, there were no real sustaining commonalities. ""Psychedelic drugs could sustain cults but not a culture,"" they say; fundamental differences separated the tune-in turn-ons from the radical politicians. With the advent of legislation proscribing hallucinogens in the wake of bad trips, chromosomal damage, and birth defects, interest in the drugs declined. The text begins with a brief informative catalogue of naturally occurring or synthetic psychedelic drugs (e.g., mescaline, psilocybin, DMT, PCP) and their uses in history. A lengthy chapter describes drug effects, concentrating on LSD as the prototype and most potent; and while the anecdotes seem endless, they do illustrate the various aspects of the drug experience. There follow sections on adverse effects including ""flashbacks"" and their treatment, research and clinical findings, and potential applications. The authors argue that the time for reassessment is at hand and that the potential for clinical benefit should be legitimately explored. Their case is sufficiently convincing to warrant more study and thought.