history of psychiatry and medicine. Galen was highly influential for over 1500 years in medicine particularly advocating the use of experimentation to advance knowledge. The polymath physician Avicenna produced many insights into medicine but only became influential in Western medicine when William Harvey's elucidation of the circulatory system forced a re-evaluation of Galen's work. The French philosopher René Descartes began the dualistic debate on the division between mind and body. Johann Christian August Heinroth is credited with the origination of the term psychosomatic illness. At the beginning of the 19th century Johann Christian Reil created the term psychiatry whilst the polymath Benjamin Rush wrote Diseases of the Mind. The philosopher Spinoza's concept of conatus, Mesmer's development of hypnosis together with Charcot's refinement of this technique influenced Sigmund Freud whose development of psychoanalytic theory was to have a profound impact on the development of liaison psychiatry. Under the guidance of Alan Gregg, psychoanalysis impacted on hospital medicine through figures such as Franz Alexander, Stanley Cobb and Felix Deutsch. Edward Billings first coined the term "liaison psychiatry." The publishing of two texts A Handbook of Elementary Psychobiology and Psychiatry, by Billings, and Psychosomatic Medicine, by Edward Weiss and O. Spurgeon English, outlined the theoretical foundations for the developing field. George L. Engel was involved in the development of liaison psychiatry and coined the term Biopsychosocial model which overcame divisions created by Cartesian mind-body dualism and was to have wider repercussions on psychiatric practice. United Kingdom The Faculty of Liaison Psychiatry was established within the Royal College of Psychiatrists in 1997. The European Association for Consultation Liaison Psychiatry and Psychosomatics also produced a set of guidelines for training in Liaison Psychiatry. The American Psychiatric Association formally recognized C-L psychiatry as a subspecialty in 2004, with its own sub-specialty board exam. The profession debated about the best term for this specialty, finally settling on "Psychosomatic Medicine". A survey for NHS England in 2015 found 133 out of 179 A&E departments could not deliver the minimum core standard for 24/7 liaison psychiatry. 11 hospitals had no liaison psychiatry service, and only 35 delivered at or above the minimum standards. Collectively there was a shortage of 1,270 trained nurses and 230 trained consultants. References External links Academy of Consultation-Liaison Psychiatry American Psychosomatic Society European Association of Psychosomatic Medicine The Royal College of Psychiatrists - Faculty of Liaison Psychiatry Centre for Mental Health research into liaison psychiatry