In response to the growing number of uninsured and mounting evidence of the health consequences of being without coverage, state and federal policy-makers are developing proposals to expand health insurance coverage. Research is providing support to these efforts, and the components of successful reforms are becoming clearer. This testimony reviews the policy design decisions made under two reform plansthat being implemented in Massachusetts and the proposal recently suggested by California's governor. These approaches are used as case studies to highlight the features required to achieve significant coverage expansions and the policy challenges faced by such an undertaking.