Intended for teachers, parents, information specialists, and others interested in instructional materials for handicapped children, the manual provides a listing of descriptive words and concepts used in indexing and retrieving instructional materials within the National Instructional Materials Information System (NIMIS). Descriptors are presented in three formats: a categorical listing, an alphabetical listinq, and a rotated index; with the alphabetical listing providinq definitions for all of the terms and appropriate cross-references to related terms. Included are a list of modifiers (undefined descriptors used to identify a specific characteristic of a material) and a list of job titles which appear in the career/vocational education category. (NIMIS contains information on over 20,000 child-use, nonprint instructional materials.) (IM)