Donating kidneys to strangers is illegal in the UK. When I called the Department of Health (DoH) to ask why, they said, "You mean, strangers selling kidneys?"
"No. Just giving them away."
There was a silence: "Giving them away?"
"Yes."
"You mean, when the donor is dead?"
"No, alive."
"We'll get back to you," they said. They did, with a prepared statement: "Ultra [the Unrelated Live Transplant Regulatory Authority] insists on confirmation of an emotional relationship between a donor and a recipient." The DoH's view, they explained over the phone, is that anyone who wants to donate a kidney to a stranger must be in it for money. If they're not, they must have psychiatric problems, and so need to be protected from themselves. No one would go through such a traumatic, invasive operation for sane, altruistic reasons. When I met Ultra's chairman, Sir Roddy McSween, he said he was sympathetic to altruistic donors in general, but added that the law's the law, and any infringement would result in three months in prison and a £2,000 fine.