SCHIP programs appear to be providing broad, affordable coverage to low-income children with special health care needs (CSHCN). A significant number of states have designed special provisions to better meet the needs of CSHCN. The study, based on interviews with government officials, providers, and advocates in 18 states, also found that CSHCN may be disproportionately affected by enrollment waiting periods designed to prevent "crowd out." Waiting periods preclude families from switching their children's private coverage to SCHIP even if that coverage is very limited and/or expensive. The authors suggest changes to permit SCHIP to "wrap around" existing private coverage or exempt CSHCN from waiting period policies.