Reimbursement has become the primary mechanism through which the regulation of doctors occurs in the United States.2 To the extent that doctors cannot afford to do things they are not paid to do, and will gladly do more of those things they are paid handsomely to do, the decisions about whether, when, and how much to pay doctors for the various things they do has unwittingly become one of the most pervasive and powerful regulatory mechanisms ever devised.