We prospectively compared the efficacy of polyvinyl bougies (Savary type) passed over a guide wire and through-the-scope balloons for the dilation of peptic esophageal strictures in a randomized study. Thirty-four patients, 17 in each treatment arm, were studied. At entry, dysphagia was assessed according to a six-point scale (0, unable to swallow; 5, normal). The end-point for dilation was to size 45F or 15 mm. Discomfort during the procedure was graded on a four-point scale (0, no discomfort; 1, mild; 2, moderate; 3, severe discomfort). Follow-up visits were at 1 week, 1 month, 3 months, and every 3 months thereafter for 2 years. At the 1-week visit, the size of esophageal lumen was measured by 8-, 10-, and 12-mm pills. Both devices effectively relieved dysphagia. By life-table analysis, stricture recurrence during the first year of follow-up was similar in both groups, but during the second year, the risk of recurrence was significantly lower in patients whose strictures were dilated with balloons. Other advantages of balloons included the need for fewer treatment sessions to achieve the defined end-diameter for dilation (1.1 + 0.1 versus 1.7 + 0.2, p < .05), and less procedural discomfort ( p < .05). The differences in luminal size after dilation, measured by the barium pill test, were not significant. Ability to pass the 12-mm pill and absence of dysphagia were correlated. Our results indicate that both devices are effective in relieving dysphagia, but balloons may have a long-term advantage. (Gastrointest Endosc 1995;41:189-95.)