The inclusion of English Language Learners as a subgroup in the No Child Left Behind legislation has leant additional importance to the need for valid and efficient measures of reading for students whose first language is not English. This study examines the use of Curriculum-Based Measurement (CBM) reading fluency as a predictor of later reading performance on state accountability tests for fifth grade ELL students. The findings of this study indicate that CBM is a significant predictor of later performance on tests for accountability for ELL students as a whole, and for the individual language groups of Spanish, Hmong, and Somali. Implications for these findings are discussed. (Contains 3 tables and 1 figure.)