Due to the shortage of organs, it has been proposed that the ban on organ sales is lifted and a market-based procurement system introduced. This paper assesses four prominent proposals for how such a market could be arranged: unregulated current market, regulated current market, payment-for-consent futures market, and the family-reward futures market. These are assessed in terms of how applicable prominent concerns with organ sales are for each model. The concerns evaluated are that organ markets will crowd out altruistic donation, (...) that consent to sell organs is invalid, that sellers will be harmed, and that commodification of organs will affect human relationships in a negative way. The paper concludes that the family-reward futures market fares best in this comparison but also that it provides the weakest incentive to potential buyers. There is an inverse relationship between how applicable prominent critiques are to organ market models and the increase in available organs they can be expected to provide. (shrink)