Researchers, program administrators, and practicing clinicians explain the most recent developments in using psychedelic substances to treat psychological, physiological, and social problems. More than a decade ago, the U.S. government lifted its ban on all testing of psychedelic substances. Winkelman and Sessa now provide updated scientific research and applications of these substances, now moving into approved categories of medicine. The text is an up-to-date assessment of the latest advances in the field of psychedelic medicine, covering the use of LSD, psilocybin, MDMA, ayahuasca, and other substances to augment psychotherapies for a range of disorders. It discusses medical and psychiatric concerns, clinical efficacy and safety, ethical considerations, and neuroscience findings regarding the psychedelic compounds. Topics covered include an overview of psychiatric applications of psychedelics; treatments for addictions and depressive disorders; effects of psychedelics on inflammation and neuroplasticity; evidence for clinical applications of DMT, ayahuasca, and cannabidiol; psychedelic treatment of sociopathic disorders; microdosing psychedelics; training psychedelic therapists; and community-based harm reduction approaches to managing psychedelic crises.