For many, the extent to which blood glucose control can be lowered is limited by risk of hypoglycaemia. Hypoglycaemia is feared and carries fiscal, social and medical costs, with risk of death being associated with severe hypoglycaemia in patients with type 2 diabetes at high cardiovascular risk. In this issue of Diabetologia, Chow et al (DOI: 10.1007/s00125-015-3512-0 ) report that patients with type 2 diabetes who suffered severe hypoglycaemia during attempts to lower blood glucose intensively were more likely to be insulin deficient and/or carry markers of autoimmunity more usually associated with type 1 diabetes. This opens the question of whether biomarkers might help clinicians identify those patients at greater or lower risk of treatment-induced hypoglycaemia, allowing therapeutic targets to be modified accordingly.