Obamacare is entering a new stage. The recent announcement by United Health Care that it will stop selling insurance to individuals and families through most health insurance exchanges marks the transition. In the next stage, federal and state policy makers must decide how to use broad regulatory powers they have under the Affordable Care Act to stabilize, expand, and diversify risk pools, improve local market competition, encourage insurers to compete on product quality rather than premium alone, and promote effective risk management. In addition, insurance companies must master rate setting, plan design, and network management and effectively manage the health risk of their enrollees in order to stay profitable, and consumers must learn how to choose and use the best plan for their circumstances.

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