Greetings from San Diego, where along with several of my Fortune colleagues I am attending the inaugural Brainstorm Health conference focused on the business of health care. We’ve assembled a collection of the finest commercially minded professionals in medicine, all of whom are exploring various ways either to cure disease or otherwise make people healthier.

If there’s a consensus among the business-of-medicine types it’s that we ought to spend way more effort (and money) on the making people healthier part. David Agus, the esteemed oncologist and author (and a co-chair of the conference), says his industry needs to focus far more on preventing diseases than curing them. It makes eminent good sense to do that: stop a disease before it starts and there’d be nothing to treat. And yet, the overwhelming focus of medicine and insurance is on treatment, not prevention.

It’s a confounding problem, both in its simplicity and the paucity of fixes for it. Dana Goldman, a health economist at the University of Southern California, gives a telling example. An endocrinologist colleague told him about treating an obese patient. “The best thing for the patient would be to take him for a walk,” the doctor said. “But I don’t get paid for that.”

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There are solutions. James Park, CEO of fitness tracker Fitbit fit , reports that companies participating in his company’s employee-monitoring program on average save $1,300 per person annually on healthcare costs. (Merely tracking employees and encouraging them to be active acts as a form of preventive medicine.)

Over the course of the conference, which ends late Wednesday, we’ll be hearing about mind-blowing innovations in medical science, in particular the ways information technology helps the cause. If there’s one thing I’ve learned already, it’s that a far simpler solution, one that requires as much of a mindset change as anything else, is staring us in the face.