Glucagon like peptide 1 (GLP-1), released from enteroendocrine L-cells in the gut epithelium, plays an important role in post-prandial glucose homeostasis and appetite control. Following the recent therapeutic successes of antidiabetic drugs aimed at either mimicking GLP-1 or preventing its degradation, attention is now turning towards the L-cell, to address whether it would be both possible and beneficial to stimulate the endogenous release of GLP-1 in vivo. Understanding the mechanisms underlying GLP-1 release from L-cells is key to this type of approach, and the use of cell line models and primary L-cells has led recently to the identification of a variety of nutrient transporters, g-protein coupled receptors and intracellular signalling pathways that may underlie the physiological responses of L-cells to food ingestion.