Renal transplant is the best option of treatment of chronic kidney disease and the shortage of cadaveric donors has caused the rapid increase of living donor programs. Provided that an important proportion of the donor-recipient pairs are incompatible between them, ABO incompatibility or positive cross-match test, one of the most important challenges of last decade, has been the solution of the above mentioned problem. For it there have begun the crossed-over transplant programs (also called donors' exchange programs) in his different combinations and these kind of transplants has been consolidated by an excellent results. To eliminate the titles of anti-HLA antibodies and the isoaglutinines we have different resources, beeing the most importants plasmapheresis, the immunoadsortion, immunoglobulin infusion, Rituximab use and splenectomy. They need all of them of the concomitant use of a powerful immunosuppression and of a suitable antiinfectious prevention. The results obtained with the incompatible donors are nowadays excellent and totally comparable to the obtained ones using living compatible donors.