Dr. Hart is currently Senior Professor of Psychology and was formerly the Dean of the Graduate School of Psychology, Fuller Theological Seminary, Pasadena, California for 13 years.  He also serves as the Executive Editor and Director of International Relations  for the American Association of Christian Counselors, a 30,000 member organization with members from all around the world.

Originally trained in South Africa, he joined the faculty at the Graduate School of Psychology, Fuller Theological Seminary, in May 1973 after spending one year as a post-doctorate fellow at Fuller. He is licensed in the state of California as a psychologist and Board certified in Psychopharmacology.  He specializes in psychotherapy from a Christian orientation, the treatment of depression, anxiety and stress disorders. His major research interests are in the area of the emotional hazards of the ministry, panic disorder, stress management for leaders, and psychophysiological measures of emotion and spirituality.

He is past President of the Pasadena Area Psychological Association, past President and one of the founding members of the Biofeedback Society of California, and was the First Recipient in 1978 of the Weyerhaeuser Award for Faculty Excellence given by Fuller Theological Seminary. Dr. Hart also received the American Association of Christian Counselors' "Caregivers Award" in 1997 at the World Conference of AACC in Dallas, Texas.

Dr. Hart, often together with his wife Kathleen, lectures widely to church groups and ministers on topics of the personal life of the minister, marriage, stress in children, stress management, emotions and how to handle them from a Christian point of view, the affects of divorce on children, and the emotional hazards of ministry, focusing on the personal life of the pastor and spouse. He maintains a clinical practice seeing many ministers and their families as well as other Christian clients and continues a publishing career, writing numerous journal and magazine articles in addition to books.