DST and cyclosporine are two immunosuppressive strategies to improve first year graft survival in high MLC, one-haplotype matched, living-related donor kidney transplantation. However, each has disadvantages: The conventional strategy of DST may sensitize the recipient to donor antigens, precluding transplantation from that donor, and cyclosporine may increase graft failure due to nephrotoxicity. We used decision analysis to compare these two strategies. We assumed that the risk of sensitization by DST is 12%, that graft failure in the first year is equal in both strategies, but that the annual probability of graft failure in later years is 2.6% with DST and from 2.7% to 3.6% with cyclosporine. Patients sensitized by DST and patients with graft failure undergo dialysis while awaiting cadaveric donor transplantation using cyclosporine. Outcomes were assessed as quality-adjusted years of survival. The analysis was deliberately biased to favor DST, the conventional strategy. Quality-adjusted life expectancy for a 40-year-old patient in both strategies is from 17.7 to 19.1 years. The difference between the DST and cyclosporine strategies ranges from -0.7 to +0.6 years. Given current data on sensitization by DST, long-term cyclosporine nephrotoxicity, and deliberate biases favoring the DST strategy, we conclude that there is no substantive advantage of the DST strategy. Cyclosporine is equally efficacious for recipients of high MLC, one-haplotype matched kidney transplants, and may be preferred for transplants from more distant relatives and unrelated living donors.