This volume contains the first two lessons of a course in subject indexing based upon the Educational Resources Information Center (ERIC) Thesaurus, Lesson 1 is an introduction to indexing, containing definitions and concepts related to the theory of indexing and information retrieval as well as an introduction to the ERIC Thesaurus. Lesson 2 is about the procedures involved in indexing a document. In this lesson the problems of choosing useful indexing concepts and translating them into terms used in the ERIC Thesaurus are dealt with. Also included is a discussion of the hierarchical relationships displayed in the thesaurus, the use of identifiers, and major descriptors. The last two lessons of the course are contained in volume 3 (LI 000 816) and the appendices are in volume 1 (LI 000 815). (CM)