This guide, prepared under the direction of the Instructional Affairs Committee of the National Council of Teachers of Mathematics (NCTM), is designed to serve all educators interested in the instructional applications of computers. Its development has been marked by a continuous, conscious effort to address the needs of all educators irrespective of their areas of interest, subject matter, or present level of involvement with instructional computing. The guide meets three tasks: (1) it provides information about the location, selection, and evaluation of computerized materials; (2) it reports this information in small sections; and (3) it defines five paths, called "tour groups," for using the guide that are defined in terms of the reader's instructional computing skills and goals. The sections to the guide are titled: (1) A Guide to These Guidelines; (2) What, Why, and for Whom; (3) Obtaining Software and Documentation; (4) Getting Hardnosed about Software: Guidelines for Software Review; (5) Communicating with Posterity: Guidelines for Software Documentation; (6) Asides to the Instructional Programmer; (7) Next Steps; and (8) Extra Forms. (MP)