Heritage education is understood to be multifaceted. The way it is approached and conceived in formal educational contexts can differ according to the emphasis policy makers wish to establish. In Flanders, a region within Belgium, a curriculum reform took shape over the last seven years. This paper explores the recently introduced curriculum in Flemish secondary education, in light of Agenda 2030 for Sustainable Development. The main aim is to investigate how heritage education and sustainability fit into the newly developed curriculum framework, and the way they are interlinked on a conceptual level. The qualitative research draws on a screening of policy texts, learning outcomes, and additional interviews with policy advisors. The results show that heritage education is implicitly present. Cross-curricular opportunities are built-in and can be linked to (a) cultural awareness and expression; (b) historical consciousness; (c) citizenship; and (d) intercultural communication. Sustainable development, and more specific ESD, anchored itself firmly and more explicitly into the framework as a transversal key competence as well. However, clear connections to heritage education are not set up in the learning outcomes.