Patricia A. Fennell, MSW, LCSW-R, is an expert on chronic illness, focusing on how the experience of chronic syndromes and trauma influence the psychological, social and physical experience of the patient and the family. She developed, researched and validated the Fennell Four-Phase Model (FFPM) for understanding and treating chronic medical and mental health conditions, trauma, disability and the effects of crime. Her research on FFPM and the Fennell Four-Phase Treatment (FFPT™) model has shown that the experience of having a chronic syndrome, such as chronic pain, fatigue, autoimmune disease, cancer, depression and the aftermath of violence, often results in emotional and physical crisis, which can lead to additional symptoms and hinders the opportunity for recovery. She has authored three books on chronic illness: The Chronic Illness Workbook: Strategies and Solutions for Taking Back Your Life; Managing Chronic Illness Using the Four-Phase Treatment Approach; and The Handbook of Chronic Fatigue Syndrome. She has also written numerous scholarly and lay press articles, including the chapter on Chronic Illness for the Encyclopedia of Social Work.