A useable denition of Gastroesophageal Reux Disease (GERD) is difcult to create but is necessary to guide management and research of this very common disorder which affects up to 20% of the population of the Western World [1–5]. The diagnosis of GERD requires more than solely the reux of gastric contents into the esophagus; indeed, some reux is normal in all patients. Basing the denition upon the amount of reux would be problematic because any determined threshold between physiological reux and pathological would be arbitrary [6]. In addressing this problem, an interna­tional consensus panel has devised the so-called Montreal denition of gastroesopha­geal reux disease, requiring both the objective nding of reux of gastric contents into the esophagus together with the subjective reporting of troublesome symptoms [7]. This is the most widely accepted denition of GERD in use today. Troublesome symptoms include the “typical” symptoms of heartburn and regurgitation, together with the “atypical” symptoms of cough, dysphonia, chest pain, epigastric pain, dyspha­gia, pneumonia and sinusitis and others. GERD can be the cause of all these symp­toms, but there can be many other etiologies too. Dening a disease based on subjective reporting of nonspecic symptoms is problematic and assuming reux as the cause and then treating as such, whether with lifestyle modication, antisecretory medica­tions or by antireux surgery, may be unhelpful in relief of symptoms where a non­GERD etiology is present. Objective evidence of GERD is therefore required, together with appropriate symptoms, before the diagnosis can be conrmed. Before considering surgery, this objective documentation of gastroesophageal reux is mandatory [8].