Liaison psychiatry, also known as consultative psychiatry or consultation-liaison psychiatry is the branch of psychiatry that specialises in the interface between general medicine/pediatrics and psychiatry, usually taking place in a hospital or medical setting. The role of the consultation-liaison psychiatrist is to see patients with comorbid medical conditions at the request of the treating medical or surgical consultant or team. Consultation-liaison psychiatry has areas of overlap with other disciplines including psychosomatic medicine, health psychology and neuropsychiatry. Scope Liaison psychiatry usually provides a service to patients in a general medical hospital, either inpatients, outpatients or attenders at the emergency department. Referrals are made when the treating medical team has questions about a patient's mental health, or how that patient's mental health is affecting his or her care and treatment. Typical issues include: Patients with medical conditions that cause/exacerbate psychiatric or behavioral problems, such as delirium. Supporting the management of patients with mental disorders who have been admitted for the treatment of medical problems. Assisting with assessment of the capacity of a patient to consent to treatment. Patients who may report physical symptoms as a result of a mental disorder, or patients with medically unexplained physical symptoms. Patients who may not have a psychiatric disorder but are experiencing distress related to their medical problems. Patients who have attempted suicide or self-harm. Assisting with the diagnosis, treatment and functional assessment of people with dementia, including advice on discharge planning or the need for long-term care. The psychiatric team liaises with many other services, including the treating medical team, other mental health services, social services, and community services. There is increasing interest on extending liaison psychiatry to primary care, for the management of long-term medical conditions such as diabetes mellitus. Effectiveness of liaison psychiatry Consultation-liaison psychiatry helps improve patients' coping mechanisms, treatment adherence, school/work re-integration and quality of life. An evaluation of the Rapid Assessment, Interface and Discharge (RAID) model of liaison psychiatry — employed at City Hospital, Birmingham — estimated that the service saved between 43 and 64 beds per day through reduced lengths of stay and prevention of readmission. In 2011 the Centre for Mental Health published an economic evaluation of the service, estimating savings of around £3.5 million. This was followed in 2012 by the publication of a report recommending that every NHS hospital should have a liaison psychiatry service as standard. History The history of liaison psychiatry is partly a