Deinstitutionalisation (or deinstitutionalization) is the process of replacing long-stay psychiatric hospitals with less isolated community mental health services for those diagnosed with a mental disorder or developmental disability. In the 1950s and 1960s, it led to the closure of many psychiatric hospitals, as patients were increasingly cared for at home, in halfway houses, group homes, and clinics, in regular hospitals, or not at all.
Deinstitutionalisation works in two ways. The first focuses on reducing the population size of mental institutions by releasing patients, shortening stays, and reducing both admissions and readmission rates. The second focuses on reforming psychiatric care to reduce (or avoid encouraging) feelings of dependency, hopelessness and other behaviours that make it hard for patients to adjust to a life outside of care.