Esophageal adenocarcinoma is a rare cancer that is increasing rapidly in incidence. Because gastroesophageal reflux disease (GERD) is a risk factor for the development of this cancer, endoscopic screening of individuals with GERD symptoms and endoscopic surveillance of those who are found to have Barrett's esophagus (BE), the presumed precursor to adenocarcinoma, have been proposed. Although no direct data support endoscopic screening or surveillance, several lines of indirect evidence are available. We apply a set of criteria for the evaluation of screening programs to endoscopic screening of subjects with reflux and endoscopic surveillance of subjects with BE. A critical examination of the data supporting these practices shows that considerable gaps exist in our knowledge regarding endoscopy as a screening test in GERD, making us unable to support this practice based on current evidence. Although no controlled trials exist to substantiate the effectiveness of surveillance programs for subjects with BE, some stronger indirect evidence does support this practice. However, further studies are necessary to substantiate the effectiveness and cost-effectiveness of endoscopic surveillance in BE. Based on the currently available data, consideration should be given to expanding the intervals between endoscopic surveillance sessions.