This study describes the Toronto, Ontario experience with autosomal dominant polycystic kidney disease (ADPKD). Patients were divided into three groups: Group 1, 19 families studied with genetic markers; Group 2, 80 pre-dialysis ADPKD patients followed by Toronto nephrologists in whom the incidence of non-renal complications and the mean age of onset of symptomatology is documented; Group 3, 4,449 individuals who entered end-stage renal failure (ESRF) in the Toronto region between the years 1981 and 1992, 320 with ADPKD and 4129 with other diseases. In this third group age of onset of ESRF, frequency, age and cause of death is compared between ADPKD and non-ADPKD. ADPKD caused by a gene different from that linked to chromosome 16 short-arm probes occurred at a frequency of between 8 and 17%. Incidence of hepatic cysts in ADPKD was similar to that of previous series, other organ involvement was underdiagnosed without deliberate screening, and incidence of symptomatic intracranial aneurysm was 1.25%. A 5% excess of patients with ADPKD died of cerebro-vascular accident. Years of survival after ESRF measured by life table analysis was significantly greater for ADPKD patients than for non-ADPKD patients. A high frequency of death due to infection still exists in ADPKD despite the reduction of invasive procedures in diagnosis and treatment, and despite the presumably improved recent methods of managing infection. The average age of onset of ESRF has been delayed by over six years, and average age of death of ADPKD patients at 63.9 years-old by 12.4 years since 1960.