Acquiring proficiency in different discourse genres involves an awareness of which syntactic structures are the most appropriate to the communicative context and purpose. This article examines two scientific research genres--conference proceedings articles and conference presentations--and compares the syntactic behaviour of a group of native speaker (NS) scientists with that of non-native speaker (NNS) scientists. The aim of the study is to investigate whether NNS scientists are able to adapt their syntax to the specific discourse requirements of each genre. The comparison is made from the point of view of information structure. In English, certain specialised syntactic structures, such as passives, clefts, inversion, and extraposition, afford a certain latitude on the discursive level, enabling the enunciator to orient the informational weight of clauses according to the effect required. The findings clearly indicate that while NS scientists manipulate information structure in a context- and genre-sensitive way, NNS scientists show much less grammatical adaptability to the information packaging requirements of the discourse genre, particularly in their oral presentations. It is argued that this has a negative impact on the rhetorical appropriacy and persuasiveness of their discourse.