We examined the validity of using Compass® test scores and high school grade point average (GPA) for placing students in first-year college courses and for identifying students at risk of not succeeding. Consistent with other research, the combination of high school GPA and Compass scores performed better than either measure used alone. Results also indicate that, relative to Compass scores, the predictive strength of high school GPA decays with student age. We recommend using multiple measures for making course placement decisions and identifying students for intervention. The following three tables are appended: (1) Estimated Variances across Institutions of Standardized Logistic Regression Coefficients in the Single-Predictor Models; (2) Estimated Variances across Institutions of Standardized Logistic Regression Coefficients in the Two-Predictor Models; and (3) Estimated Unstandardized Logistic Regression Fixed-Effects Coefficients.