We all strive to not let ourselves be trapped by appearance, to elevate form over substance. Many dentre think we even get there! However, many studies show that it is simply impossible. The author has made the experience so what was attending a prestigious piano competition. She focused her attention on the presentation and body language pianists who succeeded on stage. Still unsure of his ear, she guessed what each pianists would win a prize. This experience has been confirmed by a test with spectators who had only concert of images without sound. They also managed to spot the winners! Their posture, their insurance, their body language have finally revealed better indicators of success that their only musical talent! The author draws parallels with professional situations: we believe others evaluate and be evaluated on the expertise, the actions taken and the results achieved. In reality, it takes only 250 milliseconds our brain to make judgments about the degree of confidence we can grant a person or his skills. Yet many leaders, especially under stress, underestimate the importance of the impression that they exude. Lenjeu from where to work, as well as on the bottom of his messages on his posture, his voice, his communication. Relying both on scientific studies and examples and against-known examples of leaders, the author manages to make us that famous finger presence that we neglect too often.