Heritage interpretation lacks a unifying framework for training, planning, and delivery that integrates ethical, emotional, and practical communication skills. This article introduces Aristotle’s concept of eunoia—goodwill toward the audience—as a missing cornerstone not currently addressed in the field. It argues that eunoia can function as both an integrative ethos framework and a cognitive schema that unites existing techniques such as trust-building and dialogic responsiveness under a coherent ethical orientation. By cultivating eunoia, interpreters can enhance credibility, foster meaningful audience connections, and develop a more reflective, audience-centred practice. The article concludes with a call for future research on how eunoia can be systematically integrated into interpretation.