Sclerosing encapsulating peritonitis (SEP) is a serious complication of long-term continuous ambulatory peritoneal dialysis (CAPD) associated with obstructive symptoms and sclerosis of the peritoneal membrane. We present two cases that were successfully treated with tamoxifen and corticosteroids. Case 1: A 40-year-old patient developed end-stage renal failure (ESRF) and was managed with CAPD. He was hospitalized with symptoms of small bowel obstruction. He underwent laparotomy confirming the diagnosis of SEP. The patient was given tamoxifen 20 mg twice a day. Case 2: A 55-year-old patient with ESRF secondary to membranous glomerulonephritis. After having a cadaveric renal transplant in 1978 that failed 20 years later, the patient returned to CAPD. Six years later he had an uneventful kidney transplant and the peritoneal dialysis catheter was removed. However, 8 months later he presented with symptoms of small bowel obstruction and gross blood stained ascites. He also underwent a laparotomy that confirmed the diagnosis of SEP after biopsy. The patient was started on 20 mg of tamoxifen twice a day. Both patients' symptoms were improved gradually with an increase of serum albumin and body weight. Tamoxifen may be useful in the treatment of patients diagnosed with SEP.