Abstract
In August 2009, an ad hoc international expert committee created by the major world diabetic association, published an eagerly awaited consensus. In this, it recommended the general use of the haemoglobin A1c fraction for the diagnosis of diabetes, encouraging its standardisation and proposing a 6.5% cut-off. In this article, the diagnostic methods for diabetes, as well as the advantages, limitations and controversies of this new recommendation are reviewed.