Advocates of paid living kidney donation frequently argue that kidney sellers would benefit from paid donation under a properly regulated kidney market. The poor outcomes experienced by participants in existing markets are often entirely attributed to harmful black-market practices. This article reviews the medical and anthropological literature on the physical, psychological, social, and financial harms experienced by vendors under Iran's regulated system of donor compensation and black markets throughout the world and argues that this body of research not only documents (...) significant harms to vendors, but also provides reasons to believe that such harms would persist under a regulated system. This does not settle the question of whether or not a regulated market should be introduced, but it does strengthen the case against markets in kidneys while suggesting that those advocating such a system cannot appeal to the purported benefits to vendors to support their case. (shrink)