Patients with a diagnosis of irritable bowel syndrome (IBS) are recruited by self-referral. They are randomized to two 10 weeks of internet-delivered cognitive behavioral programs. Both programs include mindfulness training, education about how excessive avoidant and control behaviors maintain IBS symptoms, and changing of these behaviors to live a richer life. One of the programs also includes instructions on how to perform systematic exposure. The hypothesis of the study is while both groups will show improvement in terms of IBS symptom severity and quality of life, the addition of systematic exposure will lead to more improvement in symptoms.