Health insurance, and especially coverage for children, has been a subject of recent political debate in Washington State, as well as on the national stage. Policy makers and health care providers can use high-quality state-level data to assess which children lack health insurance and devise possible solutions to address this need. Illustrating the value of this approach, Child Trends analyzed 2003 data from the National Survey of Children's Health (NSCH) for a representative sample of children from Washington State. The authors find that children's access to health insurance and their health status were correlated with social and economic factors, including race/ethnicity, family income, and parent education. (Contains 1 figure.)