Heritage diplomacy is a lesser-known area of international theory and practice that has, until recently, been obscured by broader terms such as ‘cultural diplomacy’ and ‘public diplomacy’. Since the 2000s, however, emerging research from discourses of critical heritage studies, combined with a global proliferation in projects, has attracted attention. It is becoming increasingly apparent that bi- and multilateral engagements with (or through) heritage constitute a distinct diplomatic approach worthy of closer examination. This chapter explores the past, present and future of heritage diplomacy, charting historical and contemporary examples and identifying key strengths and weaknesses of this approach for practitioners and policymakers in the fields of heritage conservation, international relations, cultural studies and political science. In taking this approach, it is argued that there is a pressing need for cross-disciplinary collaboration and improved understandings between the realms of heritage and international relations.