Dr. Dennis McKenna is an ethnopharmacologist who has studied plant hallucinogens for over forty years. He is the author of many scientific papers, and co-author, with his brother Terence McKenna, He holds a doctorate from the University of British Columbia, He received post-doctoral research fellowships in the Laboratory of Clinical Pharmacology, National Institute of Mental Health, and in the Department of Neurology, Stanford University School of Medicine. He is a founding board member of the Heffter Research Institute, a non-profit organization focused on the investigation of the potential therapeutic uses of psychedelic medicines.