Marc Ettensohn, MD graduated from the University of Louisville School of Medicine and completed his psychiatry residency program at the University of Florida College of Medicine, where he served as Chief Resident for the University of Florida Department of Psychiatry. He also completed an ECT fellowship at Emory University and an administrative fellowship at the American Board of Psychiatry and Neurology. After his training, he became the medical director for the private practice, Actify of South Florida, specializing in the use of intravenous and intranasal ketamine for treatment-resistant anxiety and depressive disorders. Afterwards, he went on to develop his own private practice, Cornerstone Psychiatric Care, which continues to focus on interventional treatment for psychiatric disorders and frequently utilizes ketamine therapy. Part-time, he provides hospital consultation and psychiatric inpatient care. As a diplomate of the American Board of Psychiatry and Neurology, he serves as an ambassador and committee member for The Board. He is also an active member of the American Psychiatric Association, The Florida Psychiatric Society, and the American Society of Ketamine Physicians. He has coauthored several peer-reviewed papers in the medical literature, describing the use of ketamine for psychiatric disorders, such as Advances in Psychedelic Medicine: State-of-the-Art Therapeutic Applications* and The Rise of Ketamine in Clinical Practice.