Endoscopic mucosal resection (EMR) is an advanced endoscopic technique used to resect sessile or flat lesions confined to the superficial layers of the gastrointestinal (GI) tract, which cannot be resected by conventional endoscopic techniques. It is increasingly being recognized as a highly effective and minimally invasive alternative to surgery in the management of superficial early GI cancers. By resection through the middle or deeper part of the submucosal layer, EMR allows complete and curative resection of the diseased mucosa. This can be accomplished with minimal cost, morbidity, and mortality, and with the potential of improving the long-term quality of life of patients. Although EMR is primarily a treatment procedure, it can also be used to obtain larger and deeper tissue biopsies for diagnosis.