Much of the spending has been worth it. While the U.S. spends the most of any country by far, health care is becoming a larger part of nearly every economy. That makes sense. Better medicine is buying longer lives. Yet medical spending is so high in the U.S. that the White House now projects that if it keeps growing, it could, in 25 years, reach a third of the economy and devour 30 percent of the federal budget. That will mean higher taxes. If we can’t accept that, says Gruber, we’re going to need different technology. “Essentially, it’s how do we move from cost-increasing to cost-reducing technology? That is the challenge of the 21st century,” he says.

That is the big question in this month’s MIT Technology Review Business Report. What technologies can save money in health care? As we headed off to find them, Jonathan Skinner, a health economist at Dartmouth College, warned us that they are “as rare as hen’s teeth.”