Since 1985, 1-year graft survival in first cadaver transplants has remained constant at 78-80%. One-year graft survival rates for recipients over age 50 improved with CsA from 58% in 1981-82 to 78% in 1985-86. Survival in recipients under age 10 was 70% from 1985 to 1988, but improved to 75% in transplants performed in 1989-90. 2. The percentage of immunologic failures decreased from 75% in recipients aged 1-10 to 54% in recipients aged over 50. Thirty percent of males aged 1-10 had rejection episodes during the transplant hospitalization compared with 15% of males over age 50. These findings support earlier studies suggesting young recipients have a stronger immune response. 3. The incidence of nonimmunological failures increased from 10% in recipients under age 30 to more than 30% in patients over age 50. 4. There were no significant differences in graft outcome associated with the recipient's sex. 5. Kidneys from donors aged 1-10 or over 50 yielded poorer results than those from adult donors aged 11-50. This donor age effect was most notable in broadly sensitized, retransplanted, or HLA-B,DR-mismatched recipients. 6. Discharge serum creatinine (SCr) levels over 2.5 mg/dl were reported for more than 40% of recipients given kidneys from donors under age 5 or over age 50. When the discharge SCr was less than 2.5 mg/dl, 1-year survival was 90%, regardless of the donor age. 7. Trauma deaths accounted for 90% of kidneys from male donors aged 15-30 and 70% of comparable aged female donors. Cerebrovascular accidents were the cause of donor death for 43% and 68% of kidneys from male and female donors over 30, respectively.