Ralph Metzner, a psychotherapist who began his career working with Timothy Leary on controversial studies at Harvard involving LSD and other drugs, then spent a lifetime exploring and writing about expanded consciousness in all sorts of cultures and settings, died on March 14 at his home in Sonoma, Calif. He was 82.

His wife, Cathy Coleman, said the cause was idiopathic pulmonary fibrosis.

Dr. Metzner, who received a Ph.D. at Harvard in 1962, was a graduate student there when he began working with Dr. Leary and Richard Alpert, who were clinical psychology professors and had begun exploring therapeutic and other uses for LSD, psilocybin and similar hallucinogens. The three later collaborated on “The Psychedelic Experience: A Manual Based on the Tibetan Book of the Dead” (1964), one of the core texts of the emerging psychedelic movement.

Dr. Leary and Dr. Alpert (who later took the name Ram Dass) were both dismissed from Harvard in 1963 amid revelations that they had given hallucinogens to undergraduates as part of their research. Dr. Leary became an especially flamboyant figure in the counterculture, coining the catchphrase “Turn on, tune in, drop out.”

Dr. Metzner took a more low-profile path but continued to work in the field, teaching for decades and writing numerous books, including “Maps of Consciousness” (1971), “The Unfolding Self: Varieties of Transformative Experience” (1986) and “The Expansion of Consciousness” (2008).