The GLP-1 agonists and DPP-4 inhibitors are two novel drug classes in the treatment of type 2 diabetes. They increase insulin secretion and inhibit glucagon secretion without risk of hypoglycaemia. A decrease of glycated haemoglobin of about 1% can be expected with their use as monotherapy and as add-on therapy to the usual oral antidiabetics. In addition, GLP-1 agonists induce weight reduction at the price of gastro-intestinal side-effects and the need for subcutaneous administration. DPP-4 inhibitors can be taken orally, are well-tolerated, but weight-neutral. In the absence of relevant clinical studies, their long-term efficacy is currently unknown, as well as the clinical impact of other promising effects like beta-cell preservation.