Abstract
This article discusses some of the problems in research on aptitude treatment interactions (ATIs). Among these are the inconsistency and lack of generality in many ATI findings, especially in classroom based ATI investigations. It is suggested that such investigations may well be of limited generality due to the nature of the phenomena. Careful classification of aptitude and treatment variables between individual differences in prior achievement and instructional method avoids some of the problems of other approaches, including examining interactions between cognitive processes and instructional method. Suggestions for further ATI research are made.