In Governor Abbott's 2015 State of the State Address, he set improving early education, specifically improving public prekindergarten, as the first of his five emergency items (State of Texas Office of Governor, 2016). The 84th Texas Legislature then passed House Bill (HB) 4, which Governor Abbott signed into law in May 2015. HB 4 places renewed emphasis on high-quality prekindergarten programming through: Authorization for a new prekindergarten grant program providing additional funding to schools that meet "quality standards related to curriculum, teacher qualifications, academic performance, and family engagement"; Expansion of early childhood education reporting requirements for all Texas public schools offering prekindergarten programs beginning in the 2016-17 school year. HB 4 also added Texas Education Code (TEC) [section] 29.1545 (2015), which requires that the Texas Education Agency (TEA) conduct a joint study with the Texas Department of Family and Protective Services (DFPS) to develop recommendations regarding optimal class sizes and student-to-teacher ratios for prekindergarten classes. At the time of this report, rules or laws specifying prekindergarten class sizes and student-to-teacher ratios in Texas have not yet been established; however, the following guidance exists: TEA encourages local education agencies (LEAs) to maintain and not exceed the 22:1 ratio required for kindergarten through fourth-grade classrooms (TEC [section] 25.112, 2015); School districts or open-enrollment charter schools that offer high-quality prekindergarten programs established under the new High-Quality Prekindergarten Grant program "...must attempt to maintain an average ratio in any prekindergarten program class of not less than one certified teacher or teacher's aide for every 11 students," per the addition of TEC [section] 29.167(d) (2015) by HB 4. According to TEC [section] 29.1545 (2015), the study recommendations regarding optimal class size and student-to-teacher ratios should be based on: Data collected from prekindergarten programs, including high-quality prekindergarten programs under Subchapter E-1, reported through the Public Education Information Management System (PEIMS); and Observations of best practices and examples from effective prekindergarten programs across the state. The purpose of this report is to share findings and recommendations with the Texas Legislature from this study, conducted by ICF International and Gibson Consulting Group (study team), on behalf of the TEA and DFPS. (author abstract)