By increasing the worldwide demand for learning English as a foreign language, the need for highly qualified English teachers has been dramatically heightened. Thus, educational practitioners have been deliberately attempting to raise teacher professionalism and quality. Attempts to improve the highly qualified teachers will never succeed unless teachers are taken into account, as a whole person with their all cognitive and affective domains. Among various individual characteristics, teachers' efficacy of classroom management due to its significant role in teacher development and academic achievement has aroused much more interest. In this Book, EFL teachers' classroom management accompanying with the two influential factors on this single skill was investigated in detail.