Barrett’s esophagus (BE) is a premalignant lesion for esophageal adenocarcinoma (EAC). Development of Barrett’s esophagus is caused by biliary reflux that provokes intensive mutagenesis in stem cells of epithelium in distal esophagus and gastro-esophageal junction. Other possible cell origins of Barrett’s esophagus include stem cells of mucosal esophageal glands and their ducts, of stomach, residual embryonic cells and circulating bone marrow stem cells. Classic conception of healing of caustic lesion was replaced by idea of cytokine storm that forms inflammatory microenvironment for phenotypic shift toward intestinal metaplasia of distal esophagus. The review summarizes contemporary concepts of BE and EAC pathogenesis.