Type 2 diabetes mellitus is a complex and progressive metabolic disease involving more than 400 millions of people worldwide. The treatments need to be constantly managed to maintain appropriate glycemic control and avoiding complications. There is a wide variety of therapeutic option including oral antidiabetes drugs or new insulin on the market. The initiation of insulin treatment seems a mandatory step for a large panel of patients. Therefore, it is important to know the indications to initiate insulin treatment and the best way to associate it with antidiabetes drugs.