Diverticular disease is rare in the adolescent. Acute diverticulitis is almost never considered as a diagnosis for a young patient presenting with abdominal pain. Unfortunately, unrecognized it may be associated with significant morbidity and mortality. Also, when present, diverticulitis in the young adult is considered to be more aggressive compared to diverticulitis in older adults. Therefore, it is important to recognize, diagnose and manage diverticular disease appropriately in this age group. In tis chapter we will review the available literature on diverticula disease in the adolescent and young adult, discuss epidemiology, aetiology and pathogenesis and suggest guidelines for diagnosis and management.