How do somatic causal attributions for symptoms relate to treatment seeking behaviour in Irritable Bowel Syndrome (IBS)? How might a tendency to make somatic attributions influence an individual's cognitive representation of their illness once a diagnosis of IBS is established? In Study 1 attributions about symptoms were investigated in treatment-seekers and non treatment-seekers with IBS. Treatment-seekers had an increased tendency to make somatic attributions for both gastrointestinal symptoms and physiological symptoms characteristic of anxiety and depression, although they did not differ from non treatment-seekers in the severity of these symptoms or in their reports of psychological distress. Treatment-seekers also perceived themselves to be significantly less resistant to illness and to be significantly more likely to have poor health in the future than non treatment-seekers. In Study 2, 20 treatment seekers with chronic symptoms of IBS completed measures of mood and of the degree to which they viewed a range of symptoms as a part of their IBS. Physiological symptoms of anxiety and depression were seen as a part of IBS by a considerable proportion of the sample. Higher levels of depression were associated with an increased tendency to see physiological symptoms of anxiety and depression and even symptoms of colds as “a part of” IBS. It is concluded that a somatic attributional style may contribute both to initial treatment seeking for symptoms of IBS and the subsequent maintenance and exacerbation of the disorder once a diagnosis is established.