<p>Frame markers are essential rhetorical features in academic discourse, helping writers organise the flow of discourse. While previous research has investigated the functions and disciplinary differences of frame markers, little is known about the rhetorical features used for introducing and summarising. This study investigates the use of frame markers in academic writing across disciplines, focusing on their roles in content introduction and summarisation. Using Hyland’s (2005) framework of frame markers, this paper analyses a corpus of approximately 16 million words from three disciplines: Linguistics, Literary Studies, and Physics. The results show that Linguistics employs frame markers more frequently to introduce research aims and conclude findings compared to Literary Studies and Physics, suggesting an intensive writer-reader interaction. The rhetorical acts of introducing and summarising are closely associated with potential functions of frame markers that can be further categorised. These findings indicate that the nuanced use of frame markers for introducing and summarising necessitates further classifications beyond existing frameworks. This research enhances the understanding of disciplinary writing conventions and the role of frame markers in academic discourse, thereby informing both writing instruction and further studies in academic rhetoric.</p>