Dr. Barclay has a Ph.D. in Clinical Psychology and is a Licensed Clinical Psychologist. He is also a Professor of Psychology at Liberty University. Dr. Barclay has a diverse background. In addition to his clinical practice, he is a retired police officer serving for 20 years in the patrol division and criminal investigations bureau. He is also a veteran, having served in the U.S. Army. He is a graduate of the U.S. Army Ranger School and served in the 7th Light Infantry Division.

Dr. Barclay maintained a clinical practice for many years and developed treatment programs for juvenile offenders for the Pennsylvania Court of Common Pleas. Dr. Barclay performed his residency at Piedmont Psychiatric Center/Virginia Baptist Hospital in Lynchburg, VA.

He specializes in the treatment of ADHD, depression, anxiety, and addictions. He has received training from Harvard Medical School in the clinical and research applications of non-invasive brain stimulation techniques which he uses for ADHD, Autistic Spectrum Disorders, Addiction, Depression, and Anxiety. He is a Fellow with the American Institute of Stress. Dr. Barclay is a trained practitioner of neurofeedback therapy.

Dr. Barclay is also a staff psychologist with the international telemedicine group Doctor on Demand. In addition to clinical practice and teaching, Dr. Barclay is a published author and researcher in resilience and the clinical use of positive psychology. He is the creator of the High Capacity Model of Well-being with academic and popular publications.