Barrett's esophagus (BE) is the only known precursor for esophageal adenocarcinoma (EA). Therefore, the presence of BE identifies a high-risk group of patients who may be followed-up for early detection of EA and treated to reduce the risk for its progression. The initiating event for BE is unknown, although it is associated with chronic gastric reflux. Many of the genetic lesions involved in BE neoplastic progression are known, including loss of CDKN2A (p16) and TP53 (p53) and the development of tetraploidy and aneuploidy. Intensive endoscopic surveillance has been shown to improve survival although it can be difficult to implement in practice. Several exposures may be altered to reduce the risk for progression, including weight, diet, and the use of nonsteroidal anti-inflammatory drugs. However, most of these results should be confirmed in additional cohorts before they are used to change clinical practice.