Nowadays everybody has become familair with the procedure of blood transfusion. It is not always appreciated, however, that transfusions are equivalent to transplantations. This latter term is commonly reserved for the more spectacular transplantations of kidney, liver or heart, in which an organ from a deceased individual is given to a living human patient in need of such an organ. It has become generally accepted that before blood of a given donor can be given to a particular patient investigations have to be done to exclude a possible harmful effect of the blood on the recipient. The impressive bloodbanking institutes all over the world are in themselves convincing examples of the impor~ lance of finding compatible blood for each individual patient. ln theory compatibility tests between donor and recipient would also seem to be indicated foi solid organ transplantations just as for tranfusions. In practice compatibility tests (or in other words donor selection) are not performed by all teams involved in transplantation in humans. Major reasons for this negative attitude towards donor selection for organ grafting are probably that l) it appears to be a complicated art to the uninitiated and 2) no clear cut beneficial effect of donor selection could be demonstrated in some of the first clinical trials with human kidney transplantation. However, in a number of other studies a favourable effect of donor selection has been found. The experimental studies described in this thesis were initiated with the purpose of obtaining a model in an outbred experimental animal, in which the doubts on the usefulness of donor selection for organ transplantation could be evaluated.