Whether a second-look endoscopy after initial endoscopic hemostasis is of value is controversial. Routine surveillance endoscopy on the next day and treatment of any remaining stigmata may provide marginal benefit, but existing studies are not large enough to demonstrate significant differences. Endoscopic retreatment when patients develop rebleeding may allow emergency surgery to be avoided if successful but may endanger life if further bleeding occurs. Early data indicate that surgery can be avoided in about 75% of patients by retreatment without an increase in mortality.