• Esophageal motility was studied in 12 children with Hirschsprung's disease to see if extracolonic motor dysfunction was present in this disorder. Manometric tracings were compared with those from eight children with idiopathic megacolon and from 10 children without esophageal disease or constipation. Amplitude of esophageal contraction waves was significantly higher in children with Hirschsprung's disease than in the other two groups. Swallows that were followed by simultaneous contractions or double-peaked waves were also more common in the group with Hirschsprung's disease (subjects with Hirschsprung's disease, subjects with megacolon, and controls: 57%, 10%, and 8%, respectively). Lower esophageal sphincter characteristics did not differ among the three groups. The increase in simultaneous contractions and double-peaked waves persisted in those children who were reexamined following surgery for Hirschsprung's disease, whereas wave amplitudes fell to a level similar to that observed in the other groups. These data suggest that gastrointestinal motor dysfunction in persons with Hirschsprung's disease is not restricted to the colon, and that some of the observed abnormalities in esophageal motility do not reflect nonspecific responses to megacolon or colonic obstruction.