This article reviews the CT imaging features of a variety of nonneoplastic conditions that affect the small bowel and stresses important distinctive patterns that may help distinguish specific entities. Varoius inflammatory conditions (Crohns disease, radiation enteritis, graft versus host disease, celiac disease, Whipple disease, eosinophilic gastroenteritis, Behcet disease) as well as infiltrative disorders (amyloidosis, lymphangiectasia) and infectious diseases (Mycobacterium avium intracellulare, cytomegalovirus, cryptosporidosis) are reviewed, with key differential points emphasized. In addition, miscellaneous conditions such as ischemia, small bowel diverticulitis, and small bowel hemorrhage are discussed. Index terms: Gastrointestinal tract, diseases- Crohn disease- Ulcerative colitis- Inflammatory bowel disease- Colon- Diverticulitis- Ischemia- Bowel, diseases- Mycobacterium avium intracellulare- Computed tomography.