SUMMARY The article provides a review of the literature on the main areas of prevention of the most common complication of abdominal and thoracic surgery - the adhesion process. It is noted that adhesion processes have different clinical significance in the chest and abdominal cavities. At the same time, the experience of studying the causes of adhesion in the abdominal cavity can serve as a foundation for further research on pleural adhesions. The key factor determining the pathogenesis of adhesion formation and its prevention is fibrinolysis. Several studies have been done on this issue. Their results are promising, but most of them are contradictory and have been carried out in experimental models.