The need for donor organs is increasing more rapidly than the number of organs available from present resources using today's techniques. While efforts to improve consent rates through education and various incentives should continue, and while recovery and utilization of kidneys from donors at the extremes of age can further improve, we believe that the greatest potential for future expansion of the donor resource lies in the non-heart-beating donor. The combination of effective in situ preservation and ex vivo pulsatile preservation allows donation to occur from uncontrolled asystolic donors and provides a mechanism for both evaluation and resuscitation of the recovered kidneys. This approach, if fully utilized, can double the number of kidneys available for transplantation.