Dialysis patients are a unique population because of their chronic dependence on complex medical technology. Furthermore, their illness forces them to make critical decisions about medical care (mode of dialysis, renal transplantation, withdrawal from dialysis). The reasons dialysis patients discontinue therapy are not well understood, nor is it known whether they view dialysis therapy differently from other life-support interventions. We asked four groups of patients - in-center hemodialysis (HD), peritoneal dialysis (PD), renal transplant, and ambulatory elderly - questions about their wishes for (1) medical information, (2) participation in medical decision-making, (3) life-supporting therapy including cardiopulmonary resuscitation (CPR) and ventilatory support, and (4) stopping dialysis at the time of the study and in certain hypothetical situations. All groups wanted information and involvement in making medical decisions. Most patients desired CPR (96% of renal transplant, 76% of HD, 63% of PD, 82% of elderly), but PD patients chose CPR less often in all circumstances (at study, p = 0.004; in coma, p = 0.004; in permanent coma, p = 0.04), and they were less willing to undergo chronic ventilation (p = 0.001). PD patients were more likely to stop dialysis (p = 0.02) in coma than were HD patients. PD patients attended religious services more frequently and were less comfortable with machines, but these differences did not correlate with their decisions about life-support therapy. Dialysis patients have rarely considered stopping dialysis; they are similar to ambulatory elderly patients with regard to decisions about CPR and desire for involvement in medical decision-making. PD patients are a distinct subgroup worthy of further study.