[From the Hospício de Pedro II to the Hospital Nacional de Alienados: a hundred years of records (1841-1944)].

This research note lays out methodological approaches, documentary sources, historiographical inscription and reflections that arose from an ongoing research study entitled "From the Hospício de Pedro II to the Hospital Nacional de Alienados: a hundred years of records (1841-1944)." A group of researchers and students involved in the project have analyzed the history of the first psychiatric institution in Brazil for the period from the second half of the nineteenth century through the mid-twentieth century. They are also committed to the ideal of contributing to the organization and conservation of the documentary sources of this institution. Here we present the innovative nature of the project, especially due to its methodological approaches in combination with its focus on preserving historical documents.