http://www.nytimes.com/2015/05/03/magazine/the-great-american-kidney-swap.html?_r=1

The Great American Kidney Swap
Waiting for a donated organ is a long shot, and buying one is illegal. But sophisticated software, combined with old-fashioned selflessness, could be a solution.
By MALIA WOLLAN

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The genius of the computer algorithms driving the kidney chains is that they find the best medical matches — thus increasing the odds of a successful transplant — by decoupling donors from their intended recipients.
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