Lester Grinspoon, M.D. (Harvard Medical School, 1955) was a psychiatrist and associate professor of psychiatry at Harvard University. He was known for his groundbreaking work on the science and social policy of cannabis, psychedelics and other drugs, and his related commitment to the reformation of harmful drug policies.
He concurrently served as a senior psychiatrist at the Massachusetts Mental Health Center for 40 years and was a fellow of the American Association for the Advancement of Science and the American Psychiatric Association. He was founding editor of The American Psychiatric Association Annual Review and Harvard Mental Health Letter, holding the latter position for fifteen years.