Focusing on high school grade-point average (HSGPA) in college admissions may foster ethnic diversity and communicate the importance of high school performance. It has further been claimed that HSGPA is the best single predictor of college grades and that it is more equitable than test scores because of a smaller association with socioeconomic status (SES). Recent findings, however, suggest that HSPGA's seemingly smaller correlation with SES is a methodological artifact. In addition, it tends to produce systematic errors in the prediction of college grades. Although supplementing HSGPA with a high-school resource index can mitigate these errors, determining whether to include such an index in admissions decisions must take into account the institutional mission and the potential diversity impact.