A health or medical library is designed to assist physicians, health professionals, students, patients, consumers, medical researchers, and information specialists in finding health and scientific information to improve, update, assess, or evaluate health care. Medical libraries are typically found in hospitals, medical schools, private industry, and in medical or health associations. A typical health or medical library has access to MEDLINE, a range of electronic resources, print and digital journal collections, and print reference books. The influence of open access (OA) and free searching via Google and PubMed has a major impact on the way medical libraries operate.

The United States National Library of Medicine (NLM) is the largest biomedical library in the world, and collects and provides access to some of the best health information in the world (due to its linkage to the National Institutes of Health). The NLM maintains numerous medical and genomic databases, searchable via its Entrez search system, including MEDLINE (PubMed) and OMIM (a genetic traits database).

The largest medical library in Europe is the German National Library of Medicine (ZB MED), which also has collections in the fields of nutrition, agriculture, and environmental science. ZB MED operates as the official European supplier of full texts in response to searches conducted in the NLM's bibliographic databases such as PubMed, and also operates its own search portals.