36 37In this chapter, we are interested in how research writing may have changed in terms of the main communicative functions expressed by writers. What has been the impact of massive social changes on the ways and extent that academics convey their arguments and relationships with readers? To explore these questions, we use Biber’s (1988) multidimensional analysis, assuming that the linguistic and functional content of the dimensions it identifies indicate changes in rhetorical practices over time. We first introduce the multidimensional analysis model before discussing our results.