We examined the degree to which speakers adapt to the syntactic structures used by their interlocutor, comparing interaction between native speakers of English and a partner who was a native or nonnative speaker. In three experiments, naive participants took turns to describe and match pictures with a confederate who was a native or nonnative speaker of English. In Experiment 1, confederates produced both Prepositional Object (PO) and Double Object (DO) sentences to describe ditransitive events. We found no difference in the degree of adaptation with native and nonnative confederates. Experiment 2 explored the effect of interacting with a less flexible confederate who only produced DO sentences, some of which were ungrammatical (e.g. ''The wizard donates the golfer the cake''). We found greater adaptation towards nonnative confederates for both grammatical and ungrammatical descriptions. Experiment 3 replicated Experiment 1's design, looking at interaction with a nonnative confederate who spoke with a stronger nonnative accent. We found no difference in the degree of adaptation between Experiments 1 and 3, confirming that the greater adaptation with nonnatives in Experiment 2 was driven by the confederates' syntactic behaviour, rather than the strength of their accent. Together, our results provide evidence that adaptation is at least partly driven by listener-oriented mechanisms; speakers take into account their partner's linguistic knowledge and communicative needs when these needs are foregrounded by the communicative context.