This study tested a preliminary model of the role of dissociation and somatization in linking abuse to irritable bowel syndrome (IBS). Outpatients with IBS (N = 64) or bowel symptoms explained by physical disease (N = 61) completed questionnaires to assess recollections of abuse as children or adults and current dissociation, somatization, and emotional distress. By comparison with physically diseased patients, patients with IBS recalled more sexual abuse as children and adults, more physical abuse as children, and more psychological abuse as adults. They were more anxious and depressed, and somatized and dissociated more. Analyses indicated a causal chain linking, in turn, abuse, dissociation, somatization, and IBS. The results are consistent with a model in which childhood abuse is linked to IBS because it causes a tendency to dissociate, and because dissociation causes a general increase in physical symptoms. Future research should identify factors that explain why a generally increased level of physical symptoms should, in some patients, lead specifically to IBS.