It is broadly accepted that the success of monetary policy comes from the CBs ability to manage effectively market expectations. But without being credible, a central bank cannot properly manage expectations. Mario Draghi, the ECB president, reiterated in April 2016 how important is for a CB to be credible: “any time the credibility of a central bank is perceived as being put into question, the result is a delay in the achievement of its objectives, and therefore the need of more policy expansion.” In other words, in order to achieve effectively its monetary policy objectives, a CB must be fully credible.