"Dr. Grof is to my mind the leading practitioner and scholar of LSD psychotherapy in the world today. This book contains one of the most creative and brilliant phenomenologies and methodologies of the deeper psychodynamic processes that I know of . . . A breakthrough work . . ."
-- Jean Houston, The Foundation for Mind Research

"I know of no work that so well incorporates in one consistent whole the findings of Freud, Jung and Rank, adding fresh insights, which the methods of those psychotherapists could never have achieved. I do not doubt that many others working in this field would find Dr. Grof's discoveries a basis for a whole new strategy of research."
-- Joseph Campbell, author of The Hero with a Thousand Faces and The Masks of God

"An important book. The author has had far and away more experience in the field than anyone else and has come up with the most comprehensive and helpful framework for interpreting the data in this bewildering area that has been proposed."
-- Huston Smith, author of Religions of Man and Great Religions of the Western World

"Dr. Grof may well be foremost among world scientists working in psychedelics. The publication of his book could turn out to be a landmark in this field."
-- Walter Houston Clark, author of Chemical Ecstasy and Psychology of Religion