Barrett′s esophagus (BE) is a premalignant condition defined by the replacement of squamous epithelium by columnar epithelium in the distal part of the esophagus. Patients with BE have an increased risk of progression to esophageal adenocarcinoma (EAC). Advanced EAC has a poor 5-year survival rate. However, if EAC is diagnosed at an early stage, endoscopic treatment has proven to be a safe and effective treatment, with excellent long-term survival rates. Currently it is not possible to accurately predict which patients with BE will develop EAC. Despite promising developments in genetic and molecular biomarker research, grade of dysplasia is still the best predictor for progression to EAC. Present guidelines advise surveillance endoscopies with biopsies for BE patients to detect early neoplasia at a treatable stage. Surveillance intervals are determined by length of the BE segment and on the histopathologic diagnosis of the biopsies. Accurate histopathologic assessment of biopsies to define surveillance intervals or to decide on a treatment strategy, is therefore of the utmost importance.