Sclerosing peritonitis (ScP) is a rare but fatal complication of continuous ambulatory peritoneal dialysis (CAPD), presenting as small bowel obstruction. We have observed that only patients receiving a renal transplant survived more than a few months after the diagnosis of ScP. We now report prolonged survival of patients given immunosuppressive therapy with or without a functioning transplant. ScP was found at laparotomy in 17 Glasgow patients, 15 of whom had been exposed to chlorhexidine in alcohol. All patients discontinued CAPD after diagnosis. Within a year 12 died with recurrent bowel obstruction; none received immunosuppressive therapy. The remaining 5 patients received immunosuppressive therapy; 4 are alive between 1 and 9 years later, and one patient with widespread vascular disease died after 3 years with mesenteric ischemia. Four of the 5 received a renal transplant. One patient rejected his transplant; when immunosuppression was stopped he developed symptoms suggestive of recurrent ScP. Immunosuppressive therapy was restarted and he remains well 3 years later. The fifth patient, who did not receive a transplant, was immunosuppressed after ScP was diagnosed. She remains well 18 months later. Our experience suggests that immunosuppression is beneficial in ScP.