Since 2006 all Dutch citizens have to buy standardized individual health insurance coverage from a private insurer. Consumers have an annual choice among insurers, and insurers can selectively contract or integrate with health care providers. Subsidies make health insurance affordable for everyone. A Risk Equalization Fund compensates insurers for enrollees with predictably high medical expenses. Competing insurers are supposed to be(come) the prudent buyers of care on behalf of their insured. Although the reform of the health insurance market was a major achievement, the complementary reform of the provision market has only just begun, and is likely to be at least as complicated. The development of the insurers’ role as prudent purchasers of care is still work-in-progress. The challenge is now to successfully reform the market for the provision of health care.