Students, scholars, and genealogists can all find useful information on this website. Three links at right connect you to:
The USCIS History Office and agency history.
The USCIS Historical Reference Library, with information about library collections, services, and an online searchable catalog.
The fee-for-service USCIS Genealogy Program, which offers 1) index searches to determine what file numbers exist, if any, for a deceased immigrant and 2) copies of specific files requested by file number.