This discussion of the development and use of the ARCS model, a system for improving the motivational appeal of instructional materials, instructor behavior, and course/lesson design, begins by considering the need for a such a system. Noting that research on motivation is included in several different research fields and theoretical orientations, the paper then briefly reviews some of the alternative approaches to the study of motivation and presents a theory-based synthesis that was developed as a foundation for building a motivational design model. The four motivational categories of the model--Attention, Relevance, Confidence, and Satisfaction--are then defined and discussed in the context of major conditions that must be met for people to become and remain motivated. Three steps in the use of the ARCS model as a systematic design model interfacing with typical instructional design and development models are discussed under the headings Define, Develop, and Evaluate, and guidelines for integrating motivational strategies into instruction are suggested. Descriptions of the use of the ARCS model in two teacher training workshops with rather different groups of participants and a brief statement on the status of the model conclude this paper. (22 references) (MES)