Strong evidence of the benefits of high-quality early childhood education for all children, and of the economic returns for the nation, has led to the rapid expansion of publicly funded prekindergarten (pre-K) in recent years and an explosion of interest among the public and policymakers in how best to increase access to high-quality early learning opportunities. Despite the evidence, only a few states make pre-K available to all who want to participate. In Part I of this report, the authors describe the case for establishing a right to universal pre-K. They base their case on an examination of the important recent evidence on the educational, social, and economic benefits of pre-K for all children of eligible age, regardless of socioeconomic status or other qualifying characteristic. In addition, they summarize the significant growth in bipartisan public and political support for universal pre-K in all parts of the United States. In Part II, they define the constitutional right to universal pre-K that they seek to establish, as well as the essential elements of the educational opportunities that it would ensure. In Part III, the authors present a national overview of the current state of the law on access to pre-K services as a constitutional right, based on an analysis of constitutions and legal decisions in all 50 states, and reviews of state laws and policy documents. Then, building on these precedents, they set forth a legal strategy for establishing universal access to pre-K as a constitutional right.