Textbooks primarily are intended for the instruction of students, but they also may document the history of education for the health professions or chronicle societal viewpoints toward health. Advanced, widely recognized textbooks summarize the state of knowledge in a single field and serve as generally accepted reference tools in many disciplines.

Although NLM does not collect this category comprehensively, the Library does have an extensive collection of the principal textbooks produced for use in the education of U.S. health professionals. The collection is especially rich in advanced textbooks notable for their comprehensiveness, authority, and presentation, but the Library also collects less advanced works (such as those for allied health education, or other areas for which textbooks represent the bulk of publishing in the field), selected non-U.S. works that contain information unique to a country or culture, and others likely to have historical value.

The Library does not collect accompanying ancillary material, such as study guides, instructors' manuals, and workbooks, even when the main text has been selected.