This paper provides a comprehensive overview of lexicogrammatical markers of important lecture points and proposes a classification in terms of their interactive and textual orientation. The importance markers were extracted from the British Academic Spoken English corpus using corpus-driven and corpus-based methods. The classification is based on the markers' constituents and cotext. Most markers are interactively oriented towards the content (e.g. the point is) or listeners (e.g. "you should remember") rather than the speaker (e.g. "I should stress") or speaker and listeners jointly (e.g. "I want you to notice"). Many content-oriented markers also have secondary listener orientation (e.g. "these are the things to take home"). As regards their textual orientation, markers typically occur before the highlighted point. The analysis aims to reveal how the realizations of this metadiscursive feature reflect key characteristics of the lecture genre and suggests factors that may affect the efficacy of importance marking. The findings are useful for lecture listening and note-taking courses, lecturer training, and educational research assessing the efficacy of such discourse organizational cues.