The aim of this study was to present current knowledge about a nospecific inflammation of mucosa within segments of colon excluded from normal bowel passage called as a "diversion colitis" (DC) and to try to determine the role of factors which might modify the clinical course of DC. We also unswered the question; how to treat DC: conservatively or surgically? Our own experience with DC concerns 145 patents (which is most numerous and well exactly examined series presented in literature). In the group of patients studied, clinical signs of DC were present in over 70% of patients (early signs were low abdominal pain and tenesmus, while anal oozing appeared later). Predominating endoscopic features of DC in the group of patients studied were: a. blurring of vascular pattern (in app. 90% of patients); b. contact bleeding (in app. 80% of patients); c. mucosal oedema (in app. 60% of patients). Results of own observations and literature data indicate, that morphologic alterations in the segment of bowel excluded from normal passage are probably vasogenic consisting in atrophy and inflammation of the allergic type (this would confirm the theory about vascular etiology of DC). In our material, we have not noticed any trend toward hyperproliferation or dysplasia in the excluded segment of colon, supporting the thesis that these disturbances are largely reversible. Clinical pathology of DC does not depend on age, sex, cause and type of surgical procedure performed, mode of surgery or concomitant diseases. Authors suggested an alternative algorithm of diagnostic work-up in patients suspected of DC, and proposed that patients with a segment of bowel excluded from normal passage be subdivided into three groups: 1. Patients with no clinical, endoscopic nor morphologic signs of DC. 2. Patients with moderate signs of DC. 3. Patients with severe signs of DC. Patients in the group 1 should remain under continuous specialised supervision, because they are at risk of developing DC, while patients in the groups 2 and 3 should undergo surgical restoration of bowel continuity. This applies particularly to group 3, where indications for surgery do not stem from risk of hyperproliferation, dysplasia or malignant transformation, but from that of a massive inflammation, which may constitute a danger for patientis health and even life. Authors also underline that DC can be treated conservatively but the best and most successful and remained method of treatment of DC is the operation of decolostomy, which means restoration continuity of digestive tract.