The analysis of the institutionalization process of children and youth with special needs largely depends on the identification of key details. The institutionalization process is linked to the history of social assistance aimed at vulnerable children. Nonetheless in the case of children with special needs this analysis is more complex. The diagnosis of special need has historically created new meanings for social assistance measures. One of the consequences was that the institutionalization process had two main objectives: shelter and treatment. For this reason, the specificities of the institutionalization of children with special needs must be understood through the correlation between the history of social assistance of destitute children and the gradual development of psychiatric studies. The influence of the psychiatric studies in creating new concepts about the institutionalization of children is analyzed in this dissertation through the principles that guided European psychiatric studies during the 19th century, and influenced Brazilian disciplines. The major contribution of this study is, therefore, the analysis of these influences through the psychiatric shelter shyntesis according to the systems proposed by Robert Castel. The use of this analytical tool to study the institutionalization process of children with special needs was based on the study From Confinement to Care: Changing the Practices of Institutional Care for Children and Youth with Special Needs in the State of Rio de Janeiro, carried out by The International Center for Research and Policy on Childhood (CIESPI) in association with the Pontifical Catholic University of Rio de Janeiro (PUC-Rio), and with the support from the Brazilian Ministry of Health.