Index Medicus, edited by the National Library of Medicine, Bethesda, MD, USA, is a bibliography of the international biomedical literature and indexes more than 3,000 scientific reviews. The printed edition contains five sections: a list of indexed journals, the medical subject headings, a bibliography of medical reviews, a subject section and an author section. We explain how to conduct bibliographical searches within these five sections. The list of indexed journal shows the reader the abbreviated title in addition to the full title for writing a citation, as well as most of the important journals indexed by subject and the editing countries. Authors names are simply retrieved within the author section. Subjects are located first under the medical subject headings which contain the keywords, and then under the bibliography of medical reviews or the subject section. Despite the emergence of computer-aided literature searches, the printed data base of the Index Medicus remains a useful tool in the medical libraries around the world.