Peritonitis is a common clinical problem that occurs in patients with end stage renal disease treated by peritoneal dialysis. The aims of this study were to assess demographic aspects, rates of peritonitis, causative organisms, clinical outcomes and treatment approach for continuous ambulatory peritoneal dialysis (CAPD) -related peritonitis of patients undergoing CAPD. Seventy cases of peritonitis occurred in 55 patients treated in Infectious Diseases and Clinical Microbiology Department of Ankara Training and Research Hospital between May 2003 and April 2004 were enrolled into this study. Cloudiness of the peritoneal dialysis fluid and/or abdominal pain were considered suggestive of peritonitis and were confirmed by cell count and culture. The overall incidence of peritonitis was 2.46 ± 2.52 episodes/patient-year. Age, gender, education and profession of the patients have not been found as a risk factor in peritonitis attacks. The most common presentations of peritonitis included abdominal pain, cloudiness of the peritoneal dialysis fluid, nausea and vomiting. Peritoneal dialysate fluid white blood cell count was 1773 ± 1224/mm3 in 70 episodes. Cultures were positive in 51 (%72.9) peritonitis episodes; coagulase-negative staphylococci was the most common organism (%22.8), followed by Staphylococcus aureus (%21.4), 19 episodes (%27.2) had negative culture results. At the end of the study, 61 episodes of peritonitis in 55 patients were treated with intraperitoneal cefazolin and gentamicin protocol. Seven of the patients did not respond to initial therapy and the therapy was converted to intravenous protocol. Nine episodes were treated with IV antibiotics on admission for medical reasons (systemic infection and/or concurrent exit-side or tunnel infection). There were two deaths. Two catheters were removed and the patients were transferred to haemodialysis programme. Despite all technical improvements during recent decades, peritonitis and exit-side infections are still the major complication of CAPD. For the optimizing complication rates in individual centers, causative organisms and their antimicrobial susceptibilities must be known