The United States National Library of Medicine (NLM), operated by the United States federal government, is the world's largest medical library.

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.