Co-constructing communicative effectiveness is often challenging in English as a lingua franca (ELF): speakers have considerably less to go on in terms of shared expectations of cultural knowledge and linguistic norms. A university environment provides a convenient backdrop for sharing at least academic conventions – although these vary more than might be surmised from the uniform labelling of such event types. This paper looks into some discourse and lexicogrammatical features in academic ELF, using ELFA as the database. The data consists of spoken language, which provides direct access to the ways in which meanings are negotiated in ongoing discourse, and the speech events are typically polylogic. ELF discourse requires close cooperation from the participants, which is reflected in its enhanced explicitness among other things. The explicitation strategies speakers display facilitate mutual comprehensibility and contribute to social cohesion within the multi-participant groups. Such strategies also help overcome the potential problems participants might have in dealing with a variety of formal deviations from ordinary English as a native language (ENL). Most of the time ELF bears a very close resemblance to Standard English, but signs of incipient ELF-specific developments are also in evidence.