This study addressed the problem of insufficient information concerning the impact of variability in requirements and credentials for Florida Voluntary Prekindergarten (VPK) teachers statewide on VPK program quality. This study examined the variance in the professional credentials of VPK lead instructors in Florida school districts and whether or not this variability makes a significant difference in program quality as measured by VPK Provider Kindergarten Readiness Rates. Analysis of variance (ANOVA) and analysis of covariance (ANCOVA) statistical tests were conducted, as appropriate, for each of four research questions. Research findings indicated there was no statistically significant difference in the mean VPK Provider Kindergarten Readiness Rates based on the professional credentials for VPK lead instructors when controlling for the socio-economic status of the children enrolled at each site. Recommendations were made for future research to replicate the study using a different indicator of program quality, perhaps a measure of student progress throughout the school year. Also, the first groups of students to participate in Florida’s voluntary prekindergarten (VPK) program are now enrolled in upper elementary grades making a longitudinal study both feasible and worthwhile in evaluating the effectiveness of a largescale preschool program. The researcher further recommended that the idea of improving the qualifications of the prekindergarten workforce must persist, supported by continued research and adequate funding.