In the popular mind, d-lysergic acid diethylamide (LSD) research in psychiatry has long been associated with the CIA-funded experiments conducted by Ewen Cameron at the Allen Memorial Institute in Montreal, Quebec. Despite this reputation, a host of medical researchers in the post World War II era explored LSD for its potential therapeutic value. Some of the most widespread trials in the Western world occurred in Saskatchewan, under the direction of psychiatrists Humphry Osmond (in Weyburn) and Abram Hoffer (in Saskatoon). These medical researchers were first drawn to LSD because of its ability to produce a "model psychosis." Their experiments with the drug that Osmond was to famously describe as a "psychedelic" led them to hypothesize and promote the biochemical nature of schizophrenia. This brief paper examines the early trials in Saskatchewan, drawing on hospital records, interviews with former research subjects, and the private papers of Hoffer and Osmond. It demonstrates that, far from being fringe medical research, these LSD trials represented a fruitful, and indeed encouraging, branch of psychiatric research occurring alongside more famous and successful trials of the first generation of psychopharmacological agents, such as chlropromazine and imipramine. Ultimately, these LSD experiments failed for 2 reasons, one scientific and the other cultural. First, in the 1950s and early 1960s, the scientific parameters of clinical trials shifted to necessitate randomized controlled trials, which the Saskatchewan researchers had failed to construct. Second, as LSD became increasingly associated with student riots, antiwar demonstrations, and the counterculture, governments intervened to criminalize the drug, restricting and then terminating formal medical research into its potential therapeutic effects.