102 episodes of continuous ambulatory peritoneal dialysis (CAPD) peritonitis were studied prospectively during a 288-day period at The Queen Elizabeth Hospital, Birmingham. Organisms were isolated from 76% of the episodes, with coagulase-negative staphylococci, being the most commonly encountered organism (55%). Initial treatment consisted of intraperitoneal vancomycin and ceftazidime with subsequent adjustment on the basis of antibiotic sensitivities. With this regimen, 83% of the positive cultures became negative by 72 h, 9.8% of cases relapsed and removal of the CAPD catheter was necessary in 8 patients (7.8%). Overall, 92% of cases were cured. No adverse drug reactions were seen. This combination of antibiotics appears effective and safe in the treatment of CAPD peritonitis.