An analysis of 2376 case histories of patients with surgical infections has shown that in 827 (34.8%) patients the course of main disease was complicated by sepsis. The most frequent causes of the development of sepsis were surgical infections with localization in the abdominal cavity, lungs and mediastinum. Abdominal sepsis was diagnosed in 398 (41.7%) of patients with peritonitis. The annual growth of this category of patients was 8.3%. The outcome of abdominal sepsis was shown to depend on the score number according to scales APACHE II and SOFA, and on the timely operative treatment and beginning of antibacterial therapy.