Assuring that low-income children have health coverage would seem to be a noncontroversial and popular issue. Yet, the policy history of US children’s health insurance is full of drama, and the fate of the federal State Children’s Health Insurance Program (SCHIP) has been marked by ideological conflict and two presidential vetoes. Why? Alice Sardell answers this question through an examination of the policy legacies and decisions that shaped SCHIP, the advocacy strategies that created and sustained it, and the actors who interacted to either support or oppose its expansion. Equally, her analysis illustrates the critical importance of policy entrepreneurs, both inside and outside government, in the US policymaking process.