Most Library of Congress patrons who use the rare book collections are looking for early printed books and pamphlets. When searching for older material, whether online or in printed guides, it is critical that you use both new and old search terms. Popular vocabulary, and therefore library subject headings, have changed over time, and the Library of Congress has not had the resources to update every heading. Updating and adding to the online catalog is an ongoing process.

Some older records will still be under the heading “Negroes” or “Afro-Americans” rather than the current heading “African Americans.” “Woman” has been updated to “Women.” This pattern extends to more specific headings such as “African American women” and “African American women authors.” Refer to Library of Congress Subject Headings for an overview of subject searching at the Library. Throughout this chapter, we suggest effective search strategies for particular rare book collections and formats.