Esophageal cancer staging is a widely accepted indication for endoscopic ultrasonography (EUS). The evaluation of Barrett's esophagus (BE) with EUS is indicated only when there is high-grade dysplasia or a concern for malignancy in an endoscopic lesion. Because the options for the management of BE and early adenocarcinoma are diverse, proper selection of patients by accurate staging with EUS is critical, particularly when nonoperative management is considered. For example, patients with BE with high-grade dysplasia may be offered esophagectomy in some medical centers, but nonoperative therapies such as endoscopic ablative therapy or mucosal resection may be the preferred treatment options in other gastroenterology practices. This article discusses the scientific evidence for the use of EUS in BE or early esophageal adenocarcinoma.