What makes a good teacher? In 1991, Hartmut von Hentig attempted to answer this when he first formulated a 'Socratic oath' for the profession, and it is a question which remains relevant today. In The Socratic Oath for Teachers, Klaus Zierer revisits and reframes the concept of a teacher’s oath while also addressing challenges currently facing our societal developments in recent didactic-methodological research and fresh perspectives on the goals of the teaching profession. Referencing Socrates throughout, this short think piece proposes a professional oath for teachers that at its core is fully committed to the successful education and well-being of students. Drawing upon key research and his own experiences within education, Zierer answers the following questions, establishing how a professional oath may support teachers: What is a professional oath, and what can it do? What characterises teacher professionalism? What can be understood by teacher attitudes? Why are they crucial for a successful professional oath? Why is Socrates suitable as a guarantor for a professional oath of teachers? Why is a renewal of the Socratic Oath necessary? For whom is an oath necessary, and what must it contain? In this fascinating work, Klaus Zierer explores the principles and goals of the teaching profession and formulates theoretically sound and empirically validated principles of successful teaching. This is an essential read for any teacher, senior leader, policy maker, educationalist, or researcher who wants to learn more about what makes a good teacher.