The primary purpose of the investigation was to determine the extent to which (a) the Wisconsin Alternate Assessment (WAA) adequately measures the skills and concepts that make up the curriculum and instruction of students with significant disabilities; and (b) the WAA adequately measures the concepts and skill areas represented in Wisconsin's Model Academic Standards. Pearson correlations between the importance ratings of WAA items by the WAA Leadership Team (N = 10) and (a) the rates of WAA item applicability (i.e., the percentage of field trial cases in which each WAA item was rated applicable to the student's curriculum and instruction) and (b) individualized education program (IEP) alignment provided moderate to strong support for the correspondence between educators' instructional priorities and the actual curriculum in students' classrooms. A similar analysis of the correlation between the item importance ratings of field trial teachers (N = 40) and the frequency of WAA item applicability and IEP alignment provided similar results. Mean responses on specific items from a survey of the field trial teachers and parents also supported the correspondence between WAA items and the content of students' instruction. Expert panel members' (N = 10) ratings, gathered as part of the WAA Alignment Institute, indicated the WAA generally meets the criteria developed by Webb (1997) for acceptable alignment between assessments and curriculum expectations. Additional support for the correspondence of WAA items to Wisconsin's Model Academic Standards was provided by (a) Pearson correlations between students' WAA scores and their performance on two nationally normed rating scales and (b) mean responses to relevant items from field trial teacher and parent surveys. The following are appended: (1) WAA Participation Checklist; (2) WAA Teacher and Parent Surveys; (3) WAA Alignment Institute Item Coding Forms; and (4) WAA Alignment Institute Depth-of-Knowledge Criteria. (Contains 18 tables and 1 figure.)[The research reported in this paper was supported in part by the Wisconsin Center for Education Research, School of Education, University of Wisconsin--Madison.]