Through a combination of three needs-based public programs--Medicaid, the Children's Health Insurance Program, and tax credits for purchasing private plans in the new marketplaces--the Affordable Care Act can potentially ensure continuous coverage for many low- and moderate-income Americans. At the same time, half of individuals with incomes at less than twice the poverty level will experience a form of "churning" in their coverage; as changes occur in their life or work circumstances, they will need to switch among these three coverage sources. For many, churning will entail not only changes in covered benefits and cost-sharing, but also in care, owing to differences in provider networks. Strategies for mitigating churning's effects are complex and require time to implement. For the short term, however, the experiences of 17 states with policies aimed at smoothing transitions between health plans offer lessons for ensuring care continuity.