Guest speaker: Andrea Ens, Purdue University. This presentation outlines Canadian and American practitioners’ use of LSD, mescaline, and peyote in psychedelic conversion therapies during the postwar period. Such programs in both countries drew from widespread psychiatric faith in psychoanalysis and pharmacology in changing patient behavior, as well as shared Cold War-era cultural anxieties about sex, gender, and national security that negatively associated same-gender attraction with Communism, criminality, and psychopathy.