Charter schools represent an increasingly important form of school choice in the United States. Charter schools are public schools, with a difference. Compared to traditional public schools, they are exempted from some of the state laws and regulations that govern traditional public schools. In this way, parents come to have a greater number of choices among schools, and, due to deregulation, it is expected that the charter schools are distinct from traditional public schools. The intent is that charter schools can provide students with alternative curricula, teaching methods, and teachers who may differ in educational background and training from teachers in traditional public schools. This study, after reviewing research from across the United States, asks whether charter schools are producing higher achievement for students compared to traditional public schools. A meta-analysis was performed of the literature on charter schools and achievement, with a focus on lottery-based studies and rigorous value-added studies. Overall, for the limited set of charter schools, locations, and years that have been studied to date, charter schools are producing higher achievement gains in math relative to traditional public schools in most grade groupings. No significant differences emerged for reading achievement. However, for both math and reading the bulk of estimates are positive. Estimated charter school effects are highly variable, which likely reflects variations in the quality of education provided both at charter schools and at comparison schools, namely, local traditional public schools. Two figures and a table are appended.