Irritable bowel syndrome is a part of the family of gastrointestinal motility disorders and is characterized by abdominal pain and altered bowel habits. It is highly prevalent throughout the world with the reported prevalence rates lying between 9% and 25%. The incidence of IBS varies between different ethnic groups and the incidence has also been reported to be different in males and females. The incidence also varies between various clinical subgroups (diarrhea-predominant/constipation-predominant) of the disorder. This is a chronic condition and is the most frequent symptom complex in patients who visit gastroenterologists throughout the world. However, this is one of the least understood GI disorders as it is not a disease but a complex of symptoms. The symptoms are often severe and quite bothersome, and thus have a negative effect on the patient’s quality of life and activity level, often leading to psychiatric complications. Besides this, a substantial economic burden of the disease and its impact in terms of man hours lost per annum make it one of the most troublesome symptom complexes in medicine, which need to be solved. This book has been designed to update the readers on the extensive research done over these years and on the many new potential mechanisms of pathogenesis of this troublesome condition. The reader will also be updated on the changing epidemiology of the condition. Diagnostic approach and management of IBS have also been thoroughly reviewed with an emphasis on the recent updates in the field. Typical supportive case scenarios have been included to exemplify and highlight various points discussed. Thus, it provides an excellent opportunity to widen one’s perspective in this area.