We introduced the Ovid MEDLINE CD-ROM to a stand alone system at the Central Research Laboratories of AJINOMOTO in October 1994. One of the merits of introducing the CD-ROM includes the fact that end-users can retrieve thorough information from the MEDLINE CD-ROM without time restrictions. Compared to other MEDLINE CD-ROM products, the Ovid MEDLINE CD-ROM offers controlled vocabulary mapping capabilities, mouse-click entry for easy operation and the full MEDLINE database on only ten CD-ROM discs. In addition, the retrieval cost of the MEDLINE database is reduced.