We describe nine patients who had severe, persistent abdominal pain, vomiting, dumping, or diarrhoea several years after truncal vagotomy and gastroenterostomy had been performed for duodenal ulceration. Each patient was judged to have a bad clinical result (Visick grade 4). There was no evidence of recurrent ulceration in any of the patients, and in each the patency of the pyloric canal was confirmed radiologically or endoscopically. Each patient was treated by simply dismantling the gastroenterostomy without addition for a pyloroplasty. In one patient the surgeon suspected that a vagal trunk might have been left intact, and a revagotomy was performed by the "highly selective" technique. Postoperatively, none of the patients developed gastric retention. Symptomatic improvement occurred in eight patients, and four of them achieved perfect results (Visick grade 1). Side effects are common after vagotomy and gastroenterostomy, and are largely attributable to the presence of the gastroenterostomy stoma. Our results show that the symptoms may be alleviated by closing the gastroenterostomy, without precipitating gastric retention.