Aims of this study were, to measure detailed factors of resilience by adequate psychological instruments in a sample of Irritable Bowel Syndrome (IBS) patients and to investigate whether they are facets of the same underlying construct. To calculate a composite measure of resilience based on obtained insights concerning the structure of resilience. To test the hypothesis of a positive relation between resilience and response to therapy. And finally, to investigate differences between patients untreated or treated with Gut-directed Hypnotherapy in groups cross-sectionally and longitudinally, to test the hypothesis of a presumed increase in resilience (using the composite score) with changes in IBS symptoms, quality of life and psychological distress in parallel.