Four related research studies will evaluate patients with bleeding peptic ulcer disease (PUD). All are multicenter studies & include prospective data collection, entry onto CURE computer files & comprehensive data analysis of different treatment outcomes. Study I is a blinded, multicenter randomized controlled trial (RCT) of endoscopic hemostasis (endostasis) for bleeding PUD. Hospitalized pts with severe UGI hemorrhage & endoscopically documented PUD active bleeding (active) or non-bleeding visible vessels (VV) will be randomized to receive a) endostasis with heater probe (HP), b) endostasis with infection (INJ), or c) routine medical-surgical management (MED-SURG) without endostasis. Specific aims are to determine: 1) whether INJ stops active ulcer bleeding or prevents rebleeding from ulcers with VV during hospitalization more often than HP or MED-SURG therapy. 2) If outcomes of a bleeding episode are affected favorably or unfavorably by INJ compared to MED-SURG or HP therapy. 3) Whether there are characteristic profiles of pts who are affected most & least by INJ compared to HP or MED-SURG. Study II (LONG F/U) will prospectively evaluate the outcome of the RCT pts whenever they rebleed, every 4-6 months with clinical & laboratory examinations, & annually with endoscopies. Specific aims are to determine ulcer recurrence rates & patterns, rates of UGIB, side effects & mortality of MED, SURG, INJ or HP pts & 2) whether Surg or Med maintenance prevents recurrent PUD or rebleeding compared to no maintenance. Both new pts & those previously randomized will be followed up to five more years. Specific aims of Study III (HEALING) are 1) to evaluate the histopathology of bleeding PUD & injury patterns after HP or INJ in the ulcers that have bled & been resected & 2) to characterize the endoscopic healing patterns of bleeding PUD. The specific aim of Study IV (COST) is to prospectively evaluate and compare the direct & indirect costs of short term (RCT) & long-term management (LONG F/U) for the different treatments (MED, SURG, INJ, HP). These studies will be performed by 5 experienced CURE investigators with two study nurses, a statistician, and a data assistant. These studies will significantly expand our knowledge of the natural history of PUD hemorrhage; the role of MED, surgical, & endoscopic management; the bleeding PUD histopathology & patterns of recurrence; & the cost & economic impact of different treatments of bleeding PUD.