The research indicates that there are many benefits to pre-kindergarten participation which includes positive social and emotional benefits and academic achievement gains (Barnett et al., 2005; Cody, 1993; Neuman, 2007; U.S. Dept. of Health & Human Services, 2010). The purpose of this quantitative study was to examine the effects of the pre-kindergarten programs in the Metropolitan Nashville Public School District on the kindergarten reading readiness skills as measured by the Dynamic Indicators of Basic Early Literacy Skills (DIBELS) assessment. Determining the effects of prekindergarten on future school success will allow educators, politicians and legislators the leverage needed to advocate for additional funding to support pre-kindergarten initiatives for all students. This study examined the reading achievement gains of students in kindergarten by comparing the scores of the students who attended pre-kindergarten in MNPS compared to the students who did not attend pre-kindergarten in MNPS. The entry (August), middle of the year (December) and end of year (May) DIBELS scores from the 2008-2009 school year was compared to measure growth. The data was also analyzed to determine the differences in achievement when the following factors were controlled: (a) ethnicity, (b) socio-economic status, and (c) Limited English proficiency. This causal comparative study allowed for comparisons of reading achievement gains of kindergarten with students who participated in pre-kindergarten in MNPS and those who did not. This study used repeated measures analysis of variance (ANOVA) to test each of the four null hypotheses at the 0.05 level of significance. The analyses did find a statistically significant difference for the tested hypotheses. In particular, the pre-k participants scored significantly higher on all three measures at the beginning of kindergarten and at each assessment period (entry, mid-year and end-of-year). The results indicated that pre-kindergarten participation has the potential to ensure that students have the kindergarten reading readiness skills needed to be successful in school. As a result, research should continue to investigate the effects of pre-kindergarten experience on kindergarten reading readiness and school readiness in general by examining student performance on other assessment tools and at various grade levels. [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.]