Endoscopy has become the first and primary diagnostic and therapeutic modality in the management of patients with severe gastrointestinal bleeding. Panendoscopy, push enteroscopy, and colonoscopy provide the diagnostic, prognostic, and therapeutic elements to improve patient outcomes and to reduce morbidity and mortality from severe GI hemorrhage. Recent improvements in endoscopic hemostatic techniques and in imaging modalities using wireless capsule endoscopy suggest that diagnostic and therapeutic endoscopy will be even more important in determining patient outcomes in the future.