Grammatical aspect is a pervasive linguistic device that, according to linguistic analyses, allows speakers to encode different ways of construing events. For instance, the progressive (I am writing a book) is thought to reflect increased focus on the internal details of an event, as contrasted with the perfect (I have written a book). However, there is to date no experimental evidence that speakers in fact think about the same events differently when they describe them using progressive versus perfect aspect. We used co-speech gesture as a means to investigate what speakers' event representations are like when they produce perfect versus progressive utterances. We found that progressive event descriptions were accompanied by longer-lasting and more complex gestures than perfect event descriptions, but only when participants described events originally presented in the progressive. This evidence suggests that people are actually construing events differently when they use different grammatical aspects.