In order to evaluate the impact of ciclosporin in patients with adult onset polycystic kidney disease (ADPKD) following renal transplantation, we performed a single-center study of all (n = 65) patients with this disorder since 1978, 43 of whom received CSA (PC-CSA) with the remaining 22 treated with azathioprine (PC-AZA). An additional group of 45 age- and time-matched group of non-polycystic CSA-treated patients (nonPC-CSA) were used as a separate control group. Patient and graft survivals at 1 and 5 years were similar in PC-CSA when compared to nonPC-CSA. The commonest causes of death in both groups were cardiovascular related. The incidence of posttransplant hypertension and acute rejection were also similar. Urinary tract infections (UTIs) were, however, more frequent among PC-CSA (11 and 33% pre- and posttransplant respectively) when compared to the nonPC-CSA (2 and 17% pre- and posttransplant respectively). The PC-CSA cohort showed improved 1-year patient and graft survivals when compared to PC-AZA (94 and 70% vs. 72 and 34%) with less rejection episodes (42 vs. 88%) during the first year posttransplant but a higher mean serum creatinine at the end of the first year (2.0 vs. 1.6 mg/dl, 176.6 vs. 141.3 mumol/l). Posttransplant hypertension (67 vs. 70%) and UTIs (33 vs. 33%) were, however, similar in both groups. In summary, renal transplantation in ADPKD in the CSA era is associated with equal patient and graft survivals when compared with nonpolycystic patients of comparable age, but superior results when compared with the earlier azathioprine era.