We report the clinical and intestinal manometric findings in a group of 42 patients with chronic idiopathic intestinal pseudo-obstruction evaluated at the Mayo Clinic. The main clinical manifestations in these patients were nausea and vomiting (83%), abdominal pain (74%), distension (57%), constipation (36%), diarrhoea (29%), and urinary symptoms (17%). These symptoms preceded surgery in all patients. Air fluid levels or distended bowel loops occurred in 57% and a dilated bladder or urinary excretory pathway in 17%. All patients showed intestinal manometric abnormalities none of which are seen in healthy individuals: aberrant configuration or propagation of interdigestive motor complexes in 25 patients; bursts (greater than 2 min duration) of non-propagated phasic pressure activity in fasting and/or fed state in 30 patients; sustained incoordinated fasting pressure activity in 15 patients; and inability of an ingested meal to convert fasting into fed pattern in 28 patients. We conclude that qualitative analysis of intestinal manometry provides evidence of gut dysmotility in patients with the clinical syndrome of chronic intestinal pseudo-obstruction. These abnormalities of motility can help to establish the correct diagnosis.