Endoscopy plays a critical role in the management of patients with malignancies involving the gastrointestinal tract. Endoscopic ultrasound has provided essential staging information, made more complete by the ability to perform fine needle aspiration of suspicious lymph nodes. Novel endoscopic resection and ablative techniques are expanding therapeutic choices in premalignant and malignant conditions. Obstruction, virtually anywhere along the length of the gastrointestinal tract, can be relieved with new stents. All of these advances have made the therapeutic gastroenterologist a key member of the team managing patients with tumors of the gastrointestinal tract.