This book explains how expanding knowledge in the scientific fields of human learning and educational measurement can form the foundations of an improved approach to assessment. These advances suggest ways that the targets of assessment what students know and how well they know it as well as the methods used to make inferences about student learning can be made more valid and instructionally useful. Principles for designing and using these new kinds of assessments are presented, and examples are given to illustrate the principles. Implications for policy, practice, and research are also explored. The chapters are: (1) "Rethinking the Foundations of Assessment"; (2) "The Nature of Assessment and Reasoning from Evidence"; (3) "Advances in the Sciences of Thinking and Learning"; (4)"Contributions of Measurement and Statistical Modeling to Assessment"; (5) "Implications of the New Foundations for Assessment Design"; (6) "Assessment in Practice"; (7) "Information Technologies: Opportunities for Advancing Educational Assessment"; and (8) "Implications and Recommendations for Research, Policy, and Practice." An appendix contains biographical sketches of contributors. (Contains 542 references.) (SLD)