An inpatient unit that someone with a learning disability or mental health problem may go into for a short period, while their needs are assessed and plans are made to meet these needs. It should not become a person's permanent home. There are various reasons why a person may go into an assessment and treatment unit, including their existing placement coming to an end or their behaviour becoming a challenge for the people who care for them. The unit may be run by the NHS or by the independent sector.