This study examined pancreatic polypeptide responses to isocaloric meals of radioactively labeled glucose or starch in six normal and seven vagotomized subjects. Liquid glucose meals were ingested with the subject both erect and supine and starch meals were ingested in the upright posture as a solution and as solid balls. In normal subjects, each meal left the stomach at a similar rate and the resultant pancreatic polypeptide responses were not significantly different from one another. Emptying rates varied markedly in vagotomized subjects depending upon the physical consistency of the carbohydrate ingested and the patient's posture. Despite these differences, pancreatic polypeptide responses to each meal were almost identical. These studies demonstrate that the pancreatic polypeptide response to carbohydrate meals is still present several years after vagotomy and is unaffected by alterations in the rate of gastric emptying after vagotomy and by the physical consistency and chemical nature of the carbohydrate ingested.