A disconnect between the educational requirements of secondary institutions and postsecondary institutions often results in a large percentage of first-year college students requiring remediation (Moss & Bordelon, 2007). As such, postsecondary institutions administer tests to incoming students for placement into courses of the appropriate difficulty level. However, research on the efficacy of placement testing has revealed mixed results. Accordingly, the purpose of this study was to meta-analyze a large sample of ACCUPLACER® placement studies in order to estimate its true validity of placement decisions by correcting for statistical artifacts. Data included all ACCUPLACER placement validity studies completed through the Admitted Class Evaluation Service™ (ACES™) between 2001 and 2006. Forty-seven studies were examined, which comprised data from 17 unique institutions. When course success was defined as obtaining a grade of "B or higher," the average sample-size-weighted observed correlation between test scores and course success was 0.28; and when course success was defined as obtaining a grade of "C or higher," the average sample-size-weighted observed correlation was 0.24. After statistical artifacts were corrected, those estimates increased to 0.47 and 0.38, respectively. Furthermore, when these cut scores were applied, the percentage of students that were placed correctly ranged from 58 to 84 percent across ACCUPLACER tests. Overall, results indicated a moderate to strong relationship between ACCUPLACER scores and course success, demonstrating that ACCUPLACER test scores provide utility in terms of placing students into courses in which they are likely to succeed.