Some recent health policy proposals have included converting Medicaid into a block grant and cutting funding levels. Policymakers that support these proposals are citing the success of the Children’s Health Insurance Program (CHIP), funded by a block grant, as justification for the idea. In this analysis, CCF researchers review the role of Medicaid and CHIP in the health care system, outline the differences in their financing structures, and discuss the reasons it is not appropriate to use CHIP’s experience as a guide to what will happen if federal Medicaid funding is capped or turned into a block grant.