From 1.1.1982-30.9.1989 280 patients were treated for intraabdominal infection at the clinic for general and abdominal surgery. With regard to their prognostic significance, the extent and localization of the peritonitis, abscess formation, the number of failed organ system, patients' age, total protein, thrombocytes and leucocytes were examined in these patients. The most unfavorable prognosis showed diffuse peritonitis with a mortality rate of 47.2%. Subsequent abscessing worsened the prognosis of the illness. There was a close correlation between the number of failed organ systems at the time of hospitalization and mortality. Low total protein content or more so a necessary substitution therapy were linked to a high mortality (less than 4 g%: 81.2% mortality). A low number of thrombocytes and leucocytes and a low total protein in the serum were a sure sign for a complicated process of the illness, with these 2 situations combined, mortality was 100%. The indication for laparotomy and most of all for relaparotomy can be facilitated, if these factors are included in the decision, as their negative change are an indicator for a further existing or imminent postoperative peritonitis.