Techniques of endoscopic mucosal resection (EMR) can dramatically improve the ability to diagnose and treat superficial lesions in the gastrointestinal (GI) tract. Early cancers, submucosal tumors, and sessile polyps can be safely and completely removed in a single procedure, with long-term outcome results comparable to surgery. This is accomplished with a minimum cost, morbidity, and mortality and with little or no impact on the quality of life of patients. This article provides an overview of the techniques, indications, and outcomes of EMR in the management of GI malignancy.