The World OESO Congresses are planned to provide each time a thorough analysis of a single topic on oesophageal disease. The Seventh World Congress of EOSO was entirely devoted to Duodenogastroesophageal reflux. Clarification of the role of duodenogastroesophageal reflux in the context of oesophageal disease has been hampered for a long time by inadequate methods to detect it. The recent availability of methodology to detect either biliary or non acidic reflux has allowed to gain new insights into pathophysiology and to develop new therapeutic approaches. This book does not merely represent the proceedings of an International Congress: it collects the answers to 125 key questions, offered by basic scientists and clinicians from all over the world, all of whom have personally contributed to the topic, in order to provide a glimpse of what may lie ahead.