Multiple radiological techniques can be employed to search for the source of abdominal sepsis. Plain abdominal film can give important direct or indirect information about the origin of sepsis. Computer tomography plays the most important role. Abscesses with their typical signs (gas within encapsuled extraluminal fluid, enhancement of membrane), as well as embolism and thrombosis, can be reliably detected as sources of sepsis. Magnet resonance imaging is an alternative for patients who would otherwise be regularly exposed to X-rays (e.g. in Crohn's disease). Dependent on the clinical setting studies of the gastrointestinal tract with water-soluble contrast media are indicated (e.g. for detection of fistulas or insufficiency of an anastomosis). Angiography and scintigraphic studies are not helpful in the search for the source of abdominal sepsis.