A psychiatrist is a physician who specializes in psychiatry, the branch of medicine devoted to the diagnosis, prevention, study, and treatment of mental disorders. Psychiatrists are physicians and evaluate patients to determine whether their symptoms are the result of a physical illness, a combination of physical and mental ailments or strictly mental issues. Sometimes a psychiatrist works within a multi-disciplinary team, which may comprise clinical psychologists, social workers, occupational therapists, and nursing staff. Psychiatrists have broad training in a biopsychosocial approach to the assessment and management of mental illness.