The half-life of kidney grafts performed at Helsinki University Central Hospital has tripled from 6.5 years in 1980-84 to 17.1 years in the 1990's. 2. Delayed graft function constitutes a significant determinant of later kidney graft survival. Five-year graft survival was 81% for patients with early graft function and 71% for those with DGF. 3. High (> 350 mg/L) early (10 +/- 2 days after transplantation) cyclosporine trough levels were associated with inferior long-term graft survival. The 5-year graft survival rate was 74% compared with 86% for patients with trough levels between 250-349 mg/L. 4. Posttransplant conversion of the crossmatch test against the kidney donor, especially in association with DGF, indicates a group with significantly worse prognosis. Among 76 patients who developed antidonor antibody after transplantation, half experienced an acute rejection within 100 days and the 5-year graft survival rate was 68% compared with 83% for non-converters.