The effects of fundic vagotomy (FV) on gastric emptying in the solid and liquid phases of a meal were studied by an isotopic technique in 12 patients with duodenal ulcer. Postoperative results were compared with those obtained in the same subjects before FV and with control values obtained in an identical group of healthy subjects. Early gastric emptying (perprandial) of the two phases of the meal was enhanced by FV but the results failed to reach statistical significance. Gastric emptying of liquids, measured during the 3 h following the end of the meal, was not significantly modified by FV (half-emptying times: 62 +/- 5 min before FV, 75 +/- 8 min after and 65 +/- 7 min for controls). That of solids was significantly delayed by FV (per cent emptied by min: 0.50 +/- 0.02 p. 100 before FV, 0.40 +/- 0.03 p. 100 after, and 0.49 +/- 0.02 p. 100 for controls); this delay was found in all but one patient, but the difference was very slight. Eleven of the 12 investigated patients cured by the operation, were compared with 6 subjects presenting with post FV recurrence: gastric emptying rates of solids (0.41 +/- 0.02 p. 100/min and 0.47 +/- 0.07 p. 100/min) and half emptying times of liquids (72 +/- 10 min and 61 +/- 10 min) were not significantly different. Thus, the gastric emptying rate of an ordinary meal remains practically unchanged by FV and postoperative recurrences of duodenal ulcer cannot be explained by alteration of gastric evacuation.