Examined here is Pillow, Sandler, Braver, Wolchik, and Gersten's (this issue) strategy for screening prevention trial participants. The reviewer concludes that their selection strategy should increase the statistical power of prevention outcome studies, increase intervention cost effectiveness, and help to prevent their possible iatrogenic effects. Also, their model points up inadequacies in the longitudinal data on which most prevention strategies are based, and their model could well serve as a template for future research.