"Visible Learning" - the life project of John Hattie and the largest collection and interpretation of empirical data on the conditions for success in schools and teaching to date - comes to a clear conclusion: The decisive factor for educational success in schools lies in the attitudes of teachers. More important than what teachers do is how and why they do what they do. Consequently, he defines as the essence of his extensive studies the attitudes of successful teachers, which are meant to be anything but markers of individuality, but rather constitute the core of pedagogical expertise. In the present book "Know Your Impact! 'Visible Learning' for Classroom Practice," this idea is taken up and placed at the center. Based on ten attitudes, John Hattie and Klaus Zierer illustrate how successful teachers think.