Background: The growing interest in principal effectiveness as a means of improving teaching and student learning has led to a focus on the quality of principal preparation programs (PPPs) with calls for the adoption of PPP accountability systems similar to those of teacher preparation programs. Objective: The purpose of the present study is to examine the impact of the National Institute for School Leadership's Executive Development Program (NISL-EDP) on student achievement in a large school district in the Midwestern United States. Method: The sample included elementary and middle school students whose principals participated in the NISL-EDP compared with students in schools with non-EDP trained principals. Using propensity score matching, findings are reported from the analysis of standardized student achievement scores on the state test, the Wisconsin Knowledge and Concepts Examination. Results: Overall, in terms of state reading and mathematics achievement tests, the control students scored higher in Spring 2014 relative to their NISL counterparts. Conclusions: With respect to researchers and policymakers, the approach used to evaluating PPP effectiveness and principal effectiveness is informative and could be used as part of larger accountability systems. Student test scores do not, however, fully capture principal effectiveness and alone should not be used in making high-stakes decisions pertaining to programs or individuals.