This research investigated the impact of course placement decisions based on ACT scores or high school subject area grade averages (SGA) on ethnic and gender groups. Course success was predicted from ACT scores or SGA for four standard college freshman courses from 13 to 50 institutions. Mean between-subgroup differences in estimated probability of success and three course placement validity indices were evaluated by gender or ethnic group within course type and institution. All statistics were summarized across institutions by course type and ethnic or gender group. The results of this study showed that, from a statistical perspective, both ACT scores and SGA slightly overpredict course success for blacks and males relative to whites and females. From a practical perspective, the differences between ethnic and gender groups were small. (Contains seven references and five tables.) (Author)