Ralph Metzner has been exploring states of consciousness for more than fourty years. He earned his B.A. from Oxford University and a Ph.D. in Clinical Psychology from Harvard in 1962. In 1964 he co-authored The Psychedelic Experience with Timothy Leary and Richard Alpert. Dr. Metzner was born and spent his early years in Germany.

He served as the academic dean of the California Institute of Integral Studies from 1979-1988. He is now a psychotherapist and professor at CIIS, where he teaches courses on altered states of consciousness and green or eco-psychology. He is co-founder and president of the Green Earth Foundation, an educational organization devoted to the healing and harmonizing of the relations between humanity and the Earth.