Psychiatry is a large medical field concerned with the mind, human behaviour, harm reduction, and health and well-being. It involves assessment, management and treatment of psychiatric conditions – including psychiatric emergencies and acute conditions, as well as comorbid and chronic psychiatric conditions. It is underpinned by knowledge of internal medicine and the neurosciences, including neuroanatomy, neurophysiology, neurochemistry, and genetics and inheritance. It looks at the epidemiology, aetiology, and phenomenology of different psychiatric disorders, including their symptoms and comorbidities. It uses a range of assessment techniques, including interviewing, mental state examination, and classification, which help guide diagnosis and treatment. Treatments in psychiatry span across the social, biological, and psychological domains. Social psychiatry involves principals of recovery philosophy, awareness of stigma and psychosocial contexts, improvement of health literacy and public education, and facilitation of social support and other non-medical support services, such as counselling or group therapy. Biological treatments involve psychopharmacology prescription and management, while psychological treatments include interventions and therapies such as cognitive-behavioural therapy. Psychiatry studies basic psychology, human development, ethics, patient and carer empowerment, legislation related to mental health, and statistic and research - including critical analysis. It is a large field and is divided into the following medical specialties: General Psychiatry, Child and Adolescent Psychiatry, Psychiatry of Learning Disability, Old Age Psychiatry, Forensic Psychiatry and Medical Psychotherapy. Some of these specialties can be studied together, while General Psychiatry also includes the sub-specialties of Addiction psychiatry, Rehabilitation psychiatry and Liaison psychiatry. Psychiatric care is provided by multi-disciplinary teams of medical specialists, nurses, and community and support staff. Services are provided in hospitals, in both inpatient and outpatient settings, and in private and community clinics and institutions, including prisons and nursing homes.