In recent years there has been considerable debate over the visionary experiences induced by hallucinatory plants -- often regarded as sacred in shamanic societies -- and the related use of psychedelics in contemporary psychotherapy.

This fascinating book presents essays by many leading researchers in the field of altered states of consciousness -- presented to honour Dr. Albert Hofmann, who first discivered the extraordinary effects of LSD in 1943.

Featured here are writings on the medical use of psychedelics, the controversial issue of 'molecular mysticism', the relationship of sacrements to Gnosis, death and rebirth themes in shamanis; comparisons between meditative and psychedelic experiences, and states of tryptamine consciousness.

Among the many distinguished writers contributing to this remarkable volume are Dr. Stanislav Grof, Terence McKenna, Dr. Ralph Metzner, Professor Hanscarl Leuner, Dr. Claudio Naranjo, Claudia Muller-Ebeling and Dr. Christian Ratsch.