Colonic diverticulosis is a common condition in Western industrialized countries occurring in up to 65% of people over the age of 60 years. Only a minority of these subjects (about 10-25%) experience symptoms, fulfilling Rome III Diagnostic Criteria for irritable bowel syndrome (IBS) diagnosis (IBS-like symptoms) in 10% to 66% of cases. Symptomatic uncomplicated diverticular disease (SUDD) is a syndrome characterized by recurrent abdominal symptoms attributed to diverticula in the absence of macroscopically evident alterations other than the presence of diverticula. Due to the different peak of incidence, the overlap between SUDD and IBS is predominantly present in middle-aged or older patients. In these cases, it is very complex to establish if the symptoms are related to the presence of diverticula or due to an overlapping IBS. In fact, the link between gastrointestinal symptoms and diverticula is unclear, and the mechanism by which diverticula may induce the development of IBS-like symptoms remains to be elucidated. Currently, the etiology and pathophysiology of SUDD, particularly when IBS-like symptoms are present, are not completely understood, and thus these two entities remain a diagnostic challenge not only for the general practitioner but also for the gastroenterologist. Although many issues remain open and unresolved, some minimize the importance of a distinction of these two entities as dietary and pharmacological management may be largely overlapping.