by Atul Gawande

About the author: Physician Atul Gawande writes a regular column on science and policy for Slate, an on-line magazine.

Letting people peddle their kidneys might save lives, but the ethical price is too high.

Some people clearly are itching to do it. Consider this classified ad from Ruth Sparrow, a 55-year-old woman who was $20,000 short for a needed gallbladder operation, which ran in the May 17, 1997, St. Petersburg Times under “medical supplies”: “KIDNEY—Runs good, Taking offers. $30,000/obo.”

Someone must have called the newspaper, because it pulled the ad after three days, noting that organ selling is against federal law. That didn’t stop John Curtis, though. The 63-year-old immigrant from England managed to slip this ad into the same newspaper on May 10, 1998: “BRITISH MADE...