Barium enema remains the gold standard for demonstrating the extent and severity of colonic diverticular disease. As such, barium studies have a role in clarifying the differential diagnosis of patients with abdominal pain and altered gut function. In acute diverticulitis or suspected diverticular perforation water soluble contrast studies are preferred to barium. An alternative in this acute scenario is cross-sectional imaging by ultrasound, or more usefully computed tomography (CT). CT is especially helpful in complicated diverticular disease. Diverticular disease is a common finding at colonoscopy and is often a complicating factor in the technical performance of the procedure. In acute diverticulitis, when the risk of perforation is high, colonoscopy should not be performed. In acute diverticular haemorrhage, colonoscopic haemostatic therapy with adrenaline can be effectively performed.