The framework of threshold concepts has been used across several disciplines in higher education. Although the literature surrounding the identification of threshold concepts and their nature has flourished, their conceptualization has seemingly diverged across disciplinary lines, which should be recognized by educational developers who work with multiple disciplines. Inspired by a failed implementation of one framing of threshold concepts in Engineering, this article compares the conceptualization of threshold concepts in Engineering with their framing in Writing Studies and Information Literacy by drawing on Bernstein's notion of knowledge structures. Recommendations for educational developers are provided and situated within the framework of 'ways of thinking and practising' (WTP).