This book analyzes the performance of midshipman at the United States Naval Academy who attended preparatory school prior to admission. Multivariate models are developed to estimate the effect of a preparatory school background on several measures of midshipmen performance at the U.S. Naval Academy. The data set covers the USNA classes of 1990 through 2000. Control variables include both math and verbal Scholastic Aptitude Test (SAT) scores and the high school class-ranking percentile. Ordinary Least Squares (OLS) regression models are employed to estimate the effect of prep school background on the Order of Merit of USNA graduates, and logit models are used to estimate the effect of prep school background on the probability of graduation of a midshipman, while controlling for SAT scores and rank in high school class. The findings reveal few significant differences in performance between those midshipmen who went to preparatory school and those who did not.