On 8th November 2012, the Federal Drugs Administration in the United States received guidance from its Endocrinologic and Metabolic Drugs Advisory Committee on the application for a license for degludec insulin and its combination preparation degludec/aspart. Although the committee had voted in favour of a license there was a recommendation for a study of cardiovascular (CV) safety. This is in marked contrast to the opinion of the European Medicines Agency and Japanese authorities who were satisfied with the CV analyses. So, why should there be this divergence of opinion and who has got it right?