A review of the research literature on systematic instructional design indicates that few empirically supported guidelines exist for testing materials under development and for improving materials on the basis of feedback from potential learners. In an analysis of 17 textbooks on instructional design, eight specific aspects to be considered in developmental testing of instruction materials were identified: criterion performance, number of students, population characteristics, role of students, role of developer, method of data collection, basis of revision, and testing environment. Findings indicate: (1) some, but not universal, agreement on particular aspects of developmental testing, (2) major differences concerning the nature of developmental testing activities, (3) a plethora of general advice but few specific guidelines, (4) little linkage between guidelines for developmental testing and guidelines for revision, (5) no apparent recognition of and no reference to other areas of education and psychology which might contribute to a technology of developmental testing, and (6) little research support for the proposed guidelines. Appendices include a bibliography, flow charts, a summary table noting each author's suggestions regarding each of the eight categories of developmental testing, and a survey questionnaire on the process of developmental testing and revision of prototype instructional materials. (LH)