Clinical psychology includes the scientific study and application of psychology for the purpose of understanding, preventing, and relieving psychologically-based distress or dysfunction and to promote subjective well-being and personal development.American Psychological Association, Division 12, About Clinical PsychologyPlante, Thomas. (2005). Contemporary Clinical Psychology. New York : Wiley. ISBN 047147276X Central to its practice are psychological assessment and psychotherapy, although clinical psychologists also engage in research, teaching, consultation, forensic testimony, and program development and administration.Brain, Christine. (2002). Advanced psychology : applications, issues and perspectives. Cheltenham : Nelson Thornes. ISBN 0174900589 In many countries clinical psychology is a regulated mental health profession.

The field is often considered to have begun in 1896 with the opening of the first psychological clinic at the University of Pennsylvania by Lightner Witmer. In the first half of the 20th century, clinical psychology was focused on psychological assessment, with little attention given to treatment. This changed after the 1940s when World War II resulted in the need for a large increase in the number of trained clinicians. Since that time, two main educational models have developed—the Ph.D. science-practitioner model (focusing on research) and the Psy.D. practitioner-scholar model (focusing on clinical practice). Clinical psychologists are now considered experts in providing psychotherapy, and generally train within four primary theoretical orientations—Psychodynamic, Humanistic, Cognitive Behavioral, and Systems or Family therapy.

Clinical psychology may be confused with psychiatry, which generally has similar goals (e.g. the alleviation of mental distress), but is unique in that psychiatrists are physicians with medical degrees. As such, they tend to focus on medication-based solutions, although some also provide psychotherapeutic services as well. In practice, clinical psychologists often work in multidisciplinary teams with other professionals such as psychiatrists, occupational therapists, and social workers to bring a multimodal approach to complex patient problems.

History

main: History of psychotherapy see: Islamic psychology

In the early 19th century, one could have his or her head examined, literally, using phrenology, the study of personality by the shape of the skull. Other popular treatments included physiognomy—the study of the shape of the face—and mesmerism, Mesmer's treatment by the use of magnets. Spiritualism and Phineas Quimby's "mental healing" were also popular.Benjamin, Ludy. (2005). A history of clinical psychology as a profession in America (and a glimpse at its future). Annual Review of Clinical Psychology, 1, 1–30.