Expanding health coverage for children is at the center of policy debates as reauthorization of the 10-year-old State Children’s Health Insurance Program (SCHIP) continues. This report presents findings from Mathematica’s comprehensive seven-year evaluation of SCHIP for the Centers for Medicare and Medicaid Services. The report highlights states’ progress in conducting outreach, averting substitution, improving access, and reducing the number of uninsured low-income children. The study found that SCHIP reduced both the number and rate of uninsured children and improved children’s access to health care. From 1997 to 2003, the percentage of uninsured low-income children fell from 25 percent to 20 percent. Enrollment climbed to 6 million children in 2003 and reached 6.6 million in 2006. In addition, access to care improved, although some gaps remain for children with special health care needs and children of minority race/ethnicity.