Two hundred fifty patients with stigmata of active or recent hemorrhage from peptic ulcer were studied. Stigmata, subgrouped according to bleeding status and the presence or absence of a visible vessel, were related to the subsequent clinical course of hemorrhage. Sixty patients (24%) rebled massively and required emergency hemostasis. At the initial endoscopy a visible vessel was a relatively rare finding (21%). Less than one-third of the visible vessels rebled massively. None of the stigmata or subgroups of stigmata emerged as reliable predictors of major rebleeding. Bleeding status and ulcer site, however, were observed to influence the relative importance of a visible vessel. When a visible vessel was identified in patients with oozing, overlying clot, or gastric or duodenal ulcer, the probability of major rebleeding increased, but not significantly. However, when a visible vessel was identified in patients without other stigmata or in patients with prepyloric ulcer or older stigmata, there was a decreased probability of major rebleeding. Older stigmata was a superior predictor of self-limited hemorrhage.