Low insulin sensitivity and a selective loss of acute insulin release identify those individuals at the highest risk of developing type 2 diabetes. Normally, the rapid release of insulin after the ingestion of a meal is critical for post-prandial glucose regulation as first-phase insulin modulates suppression of endogenous glucose production and, therefore, limits meal-related plasma glucose excursions. The loss of first-phase insulin secretion contributes to the development of glucose intolerance. Indeed, postprandial hyperglycaemia represents the first and more evident perturbation of glucose homeostasis in about 60% of newly diagnosed type 2 diabetic patients. In these individuals, restoration of first-phase insulin secretion may result in more efficient inhibition of hepatic glucose production and improved glucose tolerance. In the light of these considerations, therapeutic intervention either alone or in combination with improvement of insulin resistance should be considered early in the course of the disease to prevent excessively rapid deterioration of glycaemic control.