From three different surgical departments 78 patients with purulent peritonitis are analyzed according to cause, origin, and extent of peritonitis. Operative therapy is presented. As additional antibacterial therapy the new chemotherapeutic agent, Taurolin, with antiendotoxin-effect is used. The postoperative course (temperature exceeding 38 degrees C, secondary wound healing, day of discharge, and serious complications) is correlated with pre- and intraoperative parameters; for instance, 1. postoperative fever occurs in one half of the patients, more frequently following perforation of stomach and duodenum; 2. every second patient shows secondary wound healing, this happens even more often in peritonitis arising from biliary disease or appendicitis; 3. in 29.5% of the patients serious complications arise, especially in patients with peritonitis originating in stomach, small intestine or large bowel; 4. overall mortality of 11.5% is surpassed in patients with peritonitis originating from small intestine or large bowel. The so-called peritonitis-index (calculated on the basis of pre- and intraoperative factors) shows a significant difference between survivors and patients dying during the postoperative course. In 80% of the 78 patients with purulent peritonitis taurolin was effective as a substitute for the usual antibiotics.