Plain abdominal radiograph is a simple and readily accessible but nonspecific examination for the diagnosis of abdominal diseases such as obstruction and perforation, and for the detection of retained capsules. Traditional oral contrast-based modalities such as small bowel follow-through (SBFT) and enteroclysis can detect SB strictures, fistulae, and mucosal abnormalities, However, they have been widely replaced by cross-sectional imaging techniques. The main indications for CT enterography include the investigation of suspected and confirmed Crohn’s disease, suspected small bowel bleeding, and the evaluation of suspected small bowel tumors. Magnetic resonance enterography (MRI) is a useful radiation-free test for the detection and follow-up of small bowel Crohn’s disease and in patients with Peutz-Jeghers syndrome, especially for younger patients who are expected to require repeated imaging. CT angiography is useful in localizing active bleeding by demonstrating contrast extravasation, while invasive catheter angiography can also provide therapeutic embolization. Scintigraphic studies are applied in the search of bleeding sources, ectopic gastric mucosa in a Meckel’s diverticulum, or inflammatory lesions. A combination of positron emission tomography and cross-sectional imaging (PET-CT or PET-MRI) is increasingly applied in the diagnostic of neoplastic and inflammatory diseases.