This article is only available in the PDF format. Download the PDF to view the article, as well as its associated figures and tables. Elsewhere in this issue (p 1007), there are described two human experiments utilizing donation of kidneys by living donors unrelated genetically to the recipients. In informal discussion of this issue at its meeting in Rome in the early fall of 1978, the assembled members of the International Transplantation Society overwhelmingly condemned this practice. But, on sober and more objective reflection, the wisdom and certainly the logical consistency of this position may be challenged. For this same group widely approves and encourages the practice of donation by living relatives, citing the almost negligible risk and morbidity. The objection to living unrelated donors cannot be founded on the lack of genetic relationship, for the same group actively participates in and supports utilization of organs from genetically unrelated donors who happen to be dead. Yet, the most frequently cited objection is the lower expectation of success with living unrelated donors as opposed to