Advances in the understanding of bowel appearances with high-resolution sonography have led to consideration of this technique as an important tool for bowel disease assessment. Ultrasonography may display the transformation of the intestinal wall from normal to pathological state in inflammatory diseases. Furthermore, intestinal ultrasonography may serve as a diagnostic clue if typical patterns of the bowel wall are demonstrated. Thus, Crohn's disease, ulcerative colitis, diverticulitis, or infectious ileocolitis may be specifically demonstrated in the majority of cases. Besides showing the parietal signs of inflammation, ultrasonography also shows the perigut abnormalities and may demonstrate complications such as fistulas and abscesses. Finally, with the help of Doppler, some additional information may be obtained about the activity of chronic inflammatory diseases. In clinical practice, used in combination with other imaging modalities, such as CT or endoscopy, bowel ultrasonography appears to be a non-invasive and effective diagnostic tool for the diagnosis and follow-up of Crohn's disease and ulcerative colitis.