Upper gastrointestinal bleeding (UGI) is a common medical emergency in the intensive care unit (ICU). Although it can be caused by a number of gastrointestinal disorders, its management usually follows a few simple management rules. Prior to endoscopy, the key to management is to resuscitate the patient, to determine the need for airway protection, and to assess the need for transfusions according to the American Society of Gastrointestinal Endoscopy guidelines. During endoscopy, the key to management is to recognize the cause of the bleeding and to achieve hemostasis. Following endoscopy, the key to management is to determine the need for medical therapy and to determine a proper disposition for the patient given his potential risk for rebleeding. Stress-related erosions syndrome (SRES) is a disease that usually develops in the ICU setting and is known to be associated with a high degree of morbidity and mortality. Although it is approached in the same fashion as other causes of UGI bleeding, patients tend to do better if they are recognized early and treated prophylactically. Criteria for proper patient selection and the recommended prophylactic therapy are reviewed.