Reading proficiency is the goal of many local and national reading initiatives. A key component of these initiatives is accurate and reliable reading assessment. In this high-stakes testing arena, the Dynamic Indicators of Basic Early Literacy Skills (DIBELS) has emerged as a preferred measure for identification of students at risk for reading failure. The purpose of this doctoral dissertation was to determine the utility of the DIBELS in predicting future reading achievement, as measured by the Washington Assessment of Student Learning and the Measures of Academic Progress. This is a non-experimental research study using ex post facto data. The research design was both correlational, and prediction (Gall, Gall, & Borg, 2007). The target population was primary students in grades 1-3. The study was based on longitudinal data collected in years 2006, 2007, and 2008. Data were derived from one urban school district in Washington State. The results of the research study demonstrated DIBELS measures of Oral Reading Fluency and Retell Fluency were moderate to strong predictors of reading achievement on the third grade reading WASL and MAP. This research study also indicated that the DIBELS assessment system was an unreliable measure for assessing reading achievement of certain student groups. In particular, this study determined the DIBELS mispredicted reading achievement on the WASL for students identified as English Language Learners. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]