In Western countries many residential institutions for the mentally retarded have been built since the end of 19th century. Some large-scaled public facilities accommodated as much as 5,000 to 8,000 residents. This trend persisted the middle of this century. However, institutionalism has been abandoned since the latter half of 1960's. In Japan the law for the welfare of persons with mental retardation was enacted in 1960. Thereafter the most important subject was the construction of residential institutions. Thus, Japan lags behind the United States and European countries by nearly half a century as far as the policy for the mentally retarded is concerned. International Year of Persons with Disabilities in 1981 and subsequent United Nations Decade of Persons with Disabilities provided us with motivation to change the social welfare services in Japan under the concept of normalization. At present Japanese social welfare systems are changing to community-oriented services, such as community residential facilities and day-activity centers.