The current study examined the predictive validity of oral reading fluency measures across first, second, and third grades for two reading achievement measures at the end of third grade. Oral reading fluency measures were administered to students from first grade to third. The "Texas Assessment of Knowledge and Skills" and the "Stanford Achievement Test" were also administered in the third grade. Oral reading fluency was a reliable predictor of student success on both measures. Data suggest that greater student growth in oral reading fluency is needed through the grade levels to ensure high probabilities of success on the nationally normed measure, as compared to what is needed for the state-normed measure. Implications for practice and future research are discussed. (Contains 6 tables and 1 figure.)