A growing incidence of encapsulating peritoneal sclerosis (EPS) has been reported recently in Japan, and it is now urgent to establish preventive measures against EPS development. In the present paper, we describe our observational results regarding the risk of EPS development and the characteristic features of patients with EPS, in terms of peritoneal morphology and peritoneal function as determined by peritoneal equilibration test. The ongoing working protocol for EPS prevention at Jikei University Hospital is also discussed. Our findings have revealed that long-term continuous ambulatory peritoneal dialysis (CAPD) is a risk factor for EPS development after transfer to hemodialysis from peritoneal dialysis (PD), and that, in most patients with EPS, peritoneal function is characterized by a longstanding high-transport state. The striking alterations in peritoneal morphology between patients with EPS and those with simple long-term CAPD hyperplasia include, in EPS patients, a prominent thickening of the collagenous layer of the peritoneum with neoangiogenesis and myofibroblastic transformation. Based on our findings, we established a withdrawal protocol for long-term CAPD patients, with the goal of preventing EPS. Those who have been on PD treatment for more than 72 months with high-transport state are candidates for withdrawal from PD, with performance of peritoneal lavage thereafter for a certain period of time. The clinical benefit of post-PD lavage has not yet been determined; however, the maneuver could be precluded in patients at low risk of EPS, because it was found that some patients can recover to average transport state during the period of PD withdrawal. Patients who remain high transporters with inflammatory reaction might require pharmacologic intervention, including prednisolone therapy. Further observations are required to validate our approach.