A brief discussion of the concept of validity, a description of the nature and purposes of the Iowa Tests of Educational Development (ITED), and a rationale for the inclusion of ITED results as part of the overall program evaluation of a secondary school are presented. According to the authors, the ITED can validly be used as one of the data-gathering instruments for program evaluation if the evaluation instruments are judged on the basis of the behaviors that they require of students. (Author/MV)