Four hundred and two patients with Meckel's diverticulum are reviewed. Symptoms referable to the diverticulum occurred in 68 patients or 16.9 per cent of the group. Obstruction of the small intestine, inflammation and lower gastrointestinal tract bleeding accounted for 90 per cent of the presenting symptoms. A 10.3 per cent mortality and a 17.6 per cent morbidity rate were noted for symptomatic diverticuli. Patients most likely to have symptoms develop were 40 years of age, or younger; those whose diverticuli were 2 centimeters or more in length; those whose diverticuli contained heterotopic mucosa, and, probably, those who were males. Patients more than 40 years of age with diverticuli less than 2 centimeters in length with no heterotopic mucosa and who were females constitute a lower risk group. The decision to perform an incidental Meckel's diverticulectomy should be based upon the risk of the individual patient having symptoms develop from the diverticulum.