Over the past 35 years, the public education system in the United States has undergone large-scale changes to improve student achievement, yet students' scores on standardized assessments have remained relatively flat (National Center for Educational Statistics, 2013). The purpose of this study was to determine the relationship between teachers' uses of personalized learning practices and student achievement. This study utilized a quantitative approach. Students' achievement in math and reading was measured by looking at growth from spring to the following spring on the Measure of Academic Progress reading and mathematics assessments. Using a survey instrument, classroom teachers were asked to self-report the extent to which they had implemented personalized learning practices in their classroom. For each teacher, factor scores for personalized learning practices were derived through a principal component analysis. The factor scores were incorporated into regression analyses to determine the relationship between the use of personalized learning practices and student achievement in reading and math. The results of this study confirmed previous findings which had indicated that the use of personalized learning practices varies among instructors. The findings also supported previous research which indicate that high quality teacher professional development supports teachers' implementation of personalized learning practices. Building upon these findings, recommendations include additional research measuring the impact of personalized learning practices on student achievement. [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.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]