Please post your questions and/or comments in the comments section or email them to sergey.minor AT uit.no. We will also be available on Zoom during poster session C. Link: https://zoom.us/j/896090776 We present the results of a Visual World eye-tracking study which investigated the processing of verbal aspect by Russian-speaking adults (n=124) and children (n=174) in three age groups: 3-8 y.o., 5-6 y.o. and 7-8 y.o. The participants were presented with pairs of pictures on the screen, representing an ongoing event and the corresponding completed event. While looking at the pictures, the participants heard a sentence in the past tense with either a perfective or an imperfective verb, and were asked to point to the picture that best corresponded to the sentence. The offline responses and eye-movements were recorded. The analysis of eye-movement patterns revealed that all the participant groups showed a significant effect of verbal aspect. However, the effect size was smaller for the younger children, with a clear developmental path from 3 to 8 years. Moreover, even the oldest children in our sample did not achieve adult-like processing levels. The analysis of the offline responses indicates that Russian children acquire the grammatical aspect distinction categorically, rather than on a verb by verb basis. Finally, we analyzed the time course of aspect processing. Our data support the conclusion that the processing of grammatical aspect in both adults and children happens incrementally and rapidly, comparable to the speed of lexical processing. [1]: http://