The call by two US renal specialists for active consideration of “the controlled initiation and study of potential regimens that may increase donor kidney supply in the future in a scientifically and ethically responsible manner” through cash payments is an uncomfortable challenge (Kidney International 2006;69: 960-2). However, it is not one that necessarily requires us to venture far into new territory. We already have well regulated tariffs for the valuing of various body parts, including kidneys. And the valuation that the two specialists suggest—$40 000 (£22 000; €32 000), which prize winning economist—is compatible with these tariffs.

We already permit the sale of body parts and fluids on the market model

Several “incentive models” (American Journal of Transplantation 2005;5: 15-20) already operate for the involvement of people in medical activities that do not benefit themselves directly. In the United Kingdom and the United States living donors currently have their expenses related to the operation and …