RESUMEN
A teacher plays a key role in medical training programs and is responsible for the success or failure of many education developments. This article examines the attributes of an excellent medical teacher using a three-circle model. In the inner circle are the technical skills required by the teacher as an information provider, a facilitator of learning, a curriculum developer, and an assessor. In the middle circle is how the teacher approaches their teaching—with an understanding of basic education principles, with appropriate attitudes and ethics, with an evidence-informed strategy, and working as a team member. In the outer circle is the professionalism of the teacher, evaluating their own competence and keeping up-todate with their subject and education practice.