The acute ulcer hemorrhage is one of the most frequent diagnoses in Gastroenterology. In addition to the active hemorrhage the visible ulcer vessel, even if not bleeding at present, is one of the most important prognostic criteria. Numerous controlled studies have shown that with this sign recurrent hemorrhages will occur in up to 81%, resulting in emergency surgery in up to 56% with an associated mortality of up to 21%. By a meta-analysis we could show that prophylactic endoscopic therapy can significantly reduce both the rate of recurrent hemorrhage as well as emergency surgery. If the endoscopic doppler is used as well, as diagnostic as well as follow-up examination, the effectiveness of endoscopic treatment is greatly improved. The numbers we present show that active local endoscopic therapy should be undertaken in a visible ulcer vessel.