flow by a few ml/day to achieve much higher clear-ances and, consequently, significant increases in Kt/V.The evolution of peritoneal dialysis techniques has However, while theoretically possible, this would notpermitted not only the survival of uraemic patients, be feasible in practice since it would mean carryingbut also a remarkable rehabilitation and improved out 6–10 exchanges per day. While this can be donequality of life [1–2]. in a critically ill patient admitted to the hospital, it isBefore approaching the clinical use of peritoneal absolutely impossible in patients on an ambulatorydialysis and all available techniques, one must under- regimen. For an acceptable rehabilitation in fact, thestand the nature and the characteristics of the periton- patient should not spend most of his time performingeal dialysis system. Once these characteristics have dialytic exchanges. In conclusion, a typical CAPDbeen completely discussed and understood, diVerent technique is basically dialysate flow-limited. When andialysis schedules can be proposed to personalize the attempt is made to overcome flow limitations, socialtherapy and to prescribe optimal treatment. and patient-related limitations take over and eYciencycannot be increased. The only possible way to increasethe dialysate flow without increasing the number of