A substantial body of research establishes that high quality preschool education can enhance cognitive and social development with long-term benefits for later success in school, the economy, and society more broadly. Such programs have been found to have particularly large benefits for children who are economically disadvantaged. Such children are found to have fallen behind their more advantaged peers in language and other abilities essential to school success prior to age 3, and the achievement gaps that receive so much attention on exams at 3rd grade and beyond are largely evident at kindergarten entry. Therefore, access to quality preschool education is one way in which greater equality of opportunity can be extended to children from minority and low-income families. Unfortunately, the authors' research on access to preschool in the United States finds that access--especially access to quality--is highly unequal despite the extent to which public policy at federal and state levels targets disadvantaged children. In part, this is because targeted programs too often are not high quality. Also, targeting is not as effective in reaching disadvantaged populations as policymakers naively assume. In addition, disparate and uneven state policies exacerbate inequalities. Inequality of opportunity for good early education is a particular concern for African American, Hispanic, and non-English-speaking children. This brief is organized into four main sections. The first describes the "readiness gaps" at kindergarten entry as of 2010. The remaining sections examine the extent to which there are "opportunity gaps" in the early care and education services that may be associated with those readiness gaps. The authors begin with the care arrangements at age 2 and then examine early care and education arrangements for children aged 3 and 4. Finally, they turn to state pre-K policy and its impacts on enrollment, quality standards, and funding for children ages 3 and 4.