The cost of alternative dialysis modalities for the treatment of end-stage renal disease (ESRD) was evaluated, using a societal viewpoint, in a regional nephrology program in south-western Ontario. The dialysis treatments compared were hospital hemodialysis, home hemodialysis, self-care hemodialysis, and continuous ambulatory peritoneal dialysis (CAPD). The participants were all patients treated by the same dialysis modality for the fiscal year April 1990 to March 1991. Fully allocated costs are expressed in 1993 Canadian dollars. The average costs per patient year were $88,585 for hospital hemodialysis, $55,593 for self-care hemodialysis, $44,790 for CAPD, and $32,570 for home hemodialysis. The dialysis treatment costs were $54,929 for hospital hemodialysis, $43,313 for self-care hemodialysis, $31,918 for CAPD, and $26,048 for home hemodialysis. These data quantify the magnitude of the differences between fully-allocated costs among the dialysis modalities in a regional nephrology program in Canada. The methodology used in this economic analysis can be applied to programs which differ in structure and scale. The breakdown of dialysis treatment costs into overhead, support department, personnel, supplies, and medication identifies potential areas for cost reduction strategies.