Abdominal bloating is an extremely common symptom affecting up to 96% of patients with functional gastrointestinal disorders and even 30% of the general population. To date bloating has often been viewed as being synonymous with an actual increase in abdominal girth, but recent evidence suggests that this is not necessarily the case. This review examines the relationship between the symptom of bloating and the physical sign of abdominal distension, as well as examining the epidemiology, pathophysiology and treatment options available for this debilitating aspect of the functional gastrointestinal disorders. Pathophysiological mechanisms explored include psychological factors, intestinal gas accumulation, fluid retention, food intolerance and malabsorption of sugars, weakness of abdominal musculature, and altered sensorimotor function. Treatment options are currently rather limited but include dietary changes, pharmacological approaches, probiotics and hypnotherapy.