Irritable bowel syndrome (IBS) is the best studied of the functional gastrointestinal disorders. It is a highly prevalent disorder characterized by symptoms of abdominal pain, bloating, and disordered bowel habits, which may include constipation, diarrhea, or both. IBS has a significant negative impact on patients, both financially and with regard to their quality-of-life. At present, there is no cure for IBS, and while there are a number of pharmacological therapies available to treat IBS symptoms, they are not uniformly effective. For this reason, many patients and providers are turning to dietary interventions in an attempt to ameliorate IBS symptoms. At first glance, this approach appears reasonable as dietary interventions are generally safe and side effects, including potential adverse reactions with medications, are rare. However, although dietary interventions for IBS are frequently recommended, there is a paucity of data to support their use. The goals of this article are to answer key questions about diets currently recommended for the treatment of IBS, using the best available data from the literature.