Roland Griffiths, Ph.D., is the Oliver Lee McCabe, III Professor in the Neuropsychopharmacology of Consciousness in the Departments of Psychiatry and Neurosciences and Director of the Center for Psychedelic and Consciousness Research at the Johns Hopkins University School of Medicine. His principal research focus in both clinical and preclinical laboratories has been on the behavioral and subjective effects of mood-altering drugs and he is author of over 400 scientific publications. About 20 years ago, he initiated a research program at Johns Hopkins investigating effects of the classic psychedelic substance psilocybin, the active component in "magic mushrooms." Remarkably, many research participants rate their experience of psilocybin as among the most personally meaningful of their lives, and they attribute enduring positive changes in moods, attitudes and behavior months to years after the experience. Completed and ongoing studies include those in healthy volunteers, in beginning and long-term meditators, and in religious leaders. Therapeutic studies with psilocybin include treatment of psychological distress in cancer patients, major depressive disorder, nicotine addiction, anorexia nervosa, and various other psychiatric disorders. Related studies of brain imaging and drug interactions are examining pharmacological and neural mechanisms of action. His research group has also conducted a series of survey studies characterizing various naturally-occurring and psychedelic-occasioned transformative experiences including mystical, religious, and Near Death experiences, as well as experiences claimed to reduce depression, anxiety, and substance use disorders.