The retrospective analysis of 201 children who presented with portal hypertension and were investigated by esophageal endoscopy provides the following results : 1) esophageal varices were present in 90% of the children examined; 2) the hemorrhagic risk is much higher in children with extra hepatic portal obstruction (gastrointestinal bleeding occurred in 80% of these children) than in children with intrahepatic or postsinusoidal portal hypertension (29%); 3) endoscopic signs of major portal hypertension such as tension of varices and/or congestion of the esophageal mucosa were present in virtually all children who experienced one or more episodes of gastrointestinal bleeding; 4) esophageal or gastric lesions not related to varices were responsible for bleeding in 6 children; 5) gastric varices were present in 21 of 105 children in whom a thorough gastric endoscopy was carried out; 6) partial or complete regression of varices occurred in 11 of 27 children in whom several endoscopies were performed with a follow-up of 9 months to 6 years; complete regression occurred only when varices were of small size; 7) measures used to prevent gastrointestinal bleeding in children with varices often failed when endoscopic signs of major portal hypertension were present. These results confirm the major importance of eso-gastric endoscopy in the investigation of children with portal hypertension and suggest that porto-systemic surgical shunts should be considered in children who experience at least one spontaneous episode of gastrointestinal bleeding provided the responsibility of varices is ascertained by endoscopy.