Endoscopic mucosal resection (EMR) is a useful endoscopic technique indicated for removal of superficial GI tract lesions confined to the mucosa or submucosa layers of the bowel wall, including the esophagus, stomach, duodenum, and colon. Lesion selection is key for success of the procedure and acceptable outcomes. Therefore, close visual inspection of the lesion’s size, surface pattern, color, and morphology prior to attempting EMR is critical. There are several commonly used EMR techniques, which include injection-assisted, cap-assisted, ligation-assisted, and underwater EMR. Underwater EMR is particularly helpful for non-lifting lesions due to prior attempts at biopsy or endoscopic resection.