A meta-analysis was conducted to examine the degree to which teachers' test scores and their performance in preparation programs as measured by their collegiate grade point average (GPA) predicted their teaching competence. Results from 123 studies that yielded 715 effect sizes were analyzed, and the mediating effects of test and GPA type, criterion type, teaching level, service level, and decade of data collection were considered. It was found that test scores were at best modestly related to teaching competence and that performance in preparation programs was a significantly better predictor of teaching skill. Results revealed that test scores likely do not provide additional information beyond preservice performance to safeguard the public from incompetent teaching. (Contains 3 tables and 2 notes.)