This report examines the characteristics of state special education voucher programs along with the evidence base on their impact, effectiveness, and quality. The report, which finds that the program characteristics differ considerably across states and that the research is small, dated, and often funded by voucher proponents, identifies major questions and concerns about these programs that have yet to be fully addressed by researchers or policymakers. [This report was written with assistance from Diane Stark Rentner, Matthew Frizzell, and Maria Ferguson.]