Ralph Metzner, Ph.D. was a recognized pioneer in psychological, philosophical and cross-cultural studies of consciousness and its transformations. He attended The Queen’s College, Oxford, where he obtained a BA in philosophy and psychology. Subsequently, he obtained his Ph.D. in Clinical Psychology at Harvard University and held a post-doctoral NIMH fellowship in pharmacology at the Harvard Medical School. While at Harvard he collaborated with Timothy Leary and Richard Alpert in classic studies of psychedelics in the 1960s, co-authored The Psychedelic Experience and was editor of The Psychedelic Review. He was a psychotherapist in private practice in the SF Bay Area and Professor Emeritus at the California Institute of Integral Studies in San Francisco, where he taught for 30 years.  Author of over 100 scientific papers and scholarly essays, he was the editor of and contributor to two collections of essays on the pharmacology, anthropology and phenomenology of ayahuasca (The Ayahuasca Experience, 2006)  and of psilocybe mushrooms (Sacred Mushroom of Visions, 2004). His conversational memoir of the Harvard projects in the early 1960s, Birth of a Psychedelic Culture with Ram Dass and Gary Bravo, was published in 2010. He compiled and edited a collection of essays and experiences with the empathogen MDMA, entitled Through the Gateway of the Heart (1985, 2012).

​

His books on the psychology and philosophy of transformation include Maps of Consciousness  (1971), The Unfolding Self  (1998), The Well of Remembrance  (1994) and Green Psychology  (1999). He was president and co-founder of the Green Earth Foundation, a non-profit educational organization dedicated to healing and harmonizing the relations between humanity and the Earth (www.greenearthfound.org). The Green Earth Foundation has published his writings devoted to psychoactive/psychedelic drugs:  The Toad and the Jaguar – A Field Report of Underground Research on a Visionary Medicine (2013), and Allies for Awakening – Guidelines for productive and safe experiences with entheogens (2015). His most recent books, published in 2017 are  Ecology of Consciousness – The Alchemy of Personal, Collective and Planetary Transformation (Reveal Press, 2017), and Overtones and Undercurrents – Spirituality, Reincarnation and Ancestor Influence in Entheogenic Psychotherapy (Park Street Press, 2017). Alchemical Musings was published posthumously in 2020.