Medical professionalism in today's society requires the exhibition of a range of qualities deployed in the service of patients, rather than more traditionally defined aspects such as mastery, autonomy and self-regulation. These qualities incorporate demonstrated clinical competence; aspiring to excellence in practice while demonstrating humility and recognition of personal limitations; exercising professional judgement; and maintaining a fiduciary relationship with patients by the earning and maintenance of trust. This article examines some of the theory underpinning the acquisition of medical professionalism, and considers the implications for educators across the medical education continuum, from undergraduate curricula to revalidation and continuing professional development.