“Thanks to the accountable care organizations provided for by the health-care reform act, a new system is on its way, one that will make insurance companies unnecessary,” they write. “Accountable care organizations will increase coordination of patient’s care and shift the focus of medicine away from treating sickness and toward keeping people healthy.”

My health policy crystal ball isn’t strong enough to predict whether Accountable Care Organizations will ultimately triumph over the health insurance plans we have right now. But the current health-care landscape makes it difficult to see such a takeover happening within the next eight years.

Health-care providers are indeed moving towards Accountable Care Organizations, which are health-care delivery systems that pay providers a flat fee for covering a given patient or condition rather than operating under a traditional fee-for-service model. These cost-sharing models have begun springing up across the country, as you can see in the above map that America’s Health Insurance Plans drew up. Some of the growth is likely due to the Affordable Care Act, which now has 32 health systems testing out an ACO model within Medicare.

These ACO models are showing pretty promising results. A review of eight such health plans, published in Health Affairs this past fall notes that “Some of the health plans in this study reported approximately 10 percent improvements in quality, a 15 percent decrease in readmissions and total patient days in a hospital, as well as annual savings of $336 per patient.”

So Accountable Care Organizations are indeed gaining steam, but there have also been bumps along the way in implementation. A separate Health Affairs study was meant to look at a handful of health-care systems’ experience piloting a shared-savings model. But, after three years, none of the three systems the researchers focused on were able to get the new payment model off the ground. A lot of the obstacles were technical, tied up in overhauling a fee-for-service payment system and the billing software that comes along with it.

“Support for bundled payment now is based more on conceptual appeal than experience in practice or empirical evidence,” the researchers conclude. “The early implementation experiences of the PROMETHEUS road test support both positions: Participants continue to see promise and value in the bundled payment model, but they have not yet overcome many implementation challenges.”

As, you can see in the map above, a lot of states don’t even have an ACO yet (although all have something that does look a bit like one). Accountable Care Organizations may be the future of American health care — but also looks likely that the future isn’t quite here yet.