Type 1 diabetes can be identified years before clinical diagnosis based on the detection of multiple islet autoantibodies. Based on this and depending on glycaemic status, a distinction is made between the pre-symptomatic stages 1 and 2. In scientific studies, early detection was associated with significant health benefits at the time of diagnosis and beyond. Teplizumab, an anti-CD3 monoclonal antibody, is the first drug available in the US that has been shown to delay the onset of diabetes in stage 2 by more than 2.5 years. It may soon be available in Europe. This perspective is fuelling the debate about extending population-based screening, but it also requires ethical considerations and a clear public health framework for the medical and psychological care of those affected.