Prospective analysis of the postoperative course of 1461 patients following major visceral surgery showed that postoperative complications scurred in 17.3% (253) of cases; 81% of the complications were related to the surgical procedure (surgical complications), whereas in 18.2% (46) of the patients, they complications were not related to surgery (non-surgical complications). Among septic cases, the relationship between surgical vs non-surgical complications was 141 to 29 patients, or 5:1. Early surgical reintervention was performed in all 141 patients exhibiting abdominal sepsis. Only 103 subjects (73%) in this group received additional antibiotic treatment. In contrast, all 29 patients who developed non-surgical sepsis were initially treated with antibiotics. When postoperative septic complications occur, abdominal sepsis should be considered first. Early surgical reintervention is always the treatment of choice for these complications. Antibiotics are regarded only as an adjuvant measure. For the rather rare septic complications that are not related to surgery, antibiotic therapy is used.