This spring, Acta Paediatrica is publishing five original articles underlining the importance of recurrent abdominal pain (RAP) and illustrating the scientific and diagnostic difficulties involved in understanding it. Our knowledge of organic causes is increasing with improved instruments for investigation, including 24-h pH monitoring and endoscopy, but the difficulty in how to link findings of organic abnormalities conclusively to the symptom RAP has to be further elaborated and discussed. There is an old belief that many cases of RAP have a psychogenic aetiology. Psychometric tests in past decades, however, have not supported this belief, but if the reaction primarily is one of negative stress, than we should be looking for negative stress reactions, not for psychopathology. RAP of psychosomatic origin is not just a matter of excluding organic disease, but a diagnosis that must be built on firm positive diagnostic criteria, criteria that have not yet been elaborated for a broader public.