Gastric emptying abnormalities are common in diabetic patients but correlate poorly with gastrointestinal symptoms. Poor diabetic control is more likely to lead to gastrointestinal complications of diabetes and the converse is also true. Gastric emptying may be a previously under‐recognized contributor to variations in glycaemic control in diabetes. There is evidence for both accelerated and delayed gastric emptying. More rapid gastric emptying would result in higher postprandial glucose levels and, therefore, pharmacological means to delay the rate of gastric emptying may be a new approach to slowing postprandial nutrient absorption and improving diabetic control. Hyperglycaemia reduces the rate of gastric emptying in both Type 1 (insulin‐dependent) and Type 2 (non‐insulin‐dependent) diabetic patients. The exact mechanisms responsible for the inhibitory action of hyperglycaemia on gastric emptying are unknown. There is insufficient data on the effect of hypoglycaemia on gastric emptying but one study has reported more rapid gastric emptying.