The U.S. Army Test and Evaluation Command (ATEC) is responsible for the operational testing and evaluation of Army systems in development. ATEC requested that the National Research Council form the Panel on Operational Test Design and Evaluation of the Interim Armored Vehicle (Stryker) to explore three issues concerning the initial operation test plans for the Stryker/Interim Brigade Combat Team (IBCT). First, the panel was asked to examine the measures selected to assess the performance and effectiveness of the Stryker/IBCT in comparison both to requirements and to the baseline system. Second, the panel was asked to review the test design for the Stryker/IBCT initial operational test to see whether it is consistent with best practices. Third, the panel was asked to identify the advantages and disadvantages of techniques for combining operational test data with data from other sources and types of use. In this report the panel presents findings, conclusions, and recommendations pertaining to the first two issues: measures of performance and effectiveness, and test design. The panel intends to prepare a second report that discusses techniques for combining information. Table of Contents Front Matter Executive Summary 1. Introduction 2. Test Process 3. Test Measures 4. Statistical Design 5. Data Analysis 6. Assessing the IBCT/Stryker Operational Test in a Broad Context References Appendix A: Letter Report of the Panel to the Army Test and Evalution Command Appendix B: Force Exchange Ratio, Historical Win Probability, and Winning with Decisive Force Appendix C: Biographical Sketches of Panel Members and Staff