In the light of 9 cases, the authors study the varioud radiological appearances of postoperative obstructions. These may be early, before the restoration of intestinal transit, or secondary, during the days following the restoration of transit. The authors eliminate late postoperative obstructions from this study. There are various mechanisms of postoperative obstruction: organic obstructions may be due to an adhesion but also to agglutination or incarceration of intestinal loops. Functional obstructions most often accompany a localised area of inflammation. Mixed obstructions are a special feature of the postoperative period: agglutination of loops in contact with an area of inflammation. The authors emphasize the difficulty of radiological interpretation and the frequent disagreement between radiological and surgical findings.