The objectives of this project were (1) to determine whether or not adapting instruction to student characteristics will improve the effectiveness and efficiency of training, (2) to identify the learner attributes that interact best with specific instructional treatments, and (3) to establish what must be done to create and implement a useful adaptive instructional system. The professional literature concerning adaptive teaching systems was reviewed and evaluated, and several approaches to accommodating instruction to student characteristics were identified and considered. Little empirical evidence was obtained to support the aptitude-treatment-interaction (ATI) approach, and the experimental evaluation of several alternative approaches to adaptive instruction was recommended. (Author/JEG)