This course syllabus for a continuing education course for health science librarians introduces the MEDLARS system, the MEDLINE database, and the Index Medicus. Designed to enable health science librarians to discriminate between the capabilities of manual searching and online retrieval, an overview is given of the nature and scope of MEDLINE and the Index Medicus which emphasizes the indexing methodology and characteristics of the information in each source. It is noted that, although Index Medicus and MEDLINE are used as the examples for this course, the principles of online searching and the differences between print and online resources are readily transferable to other databases and printed counterparts. In addition, parallels are drawn between various search systems which offer the MEDLINE database, and other biomedical databases offered by the National Library of Medicine are discussed. The text is supplemented by four figures, and seven supporting appendices are provided. (Author/EW)