Our study highlights how careful attention to, reflection on, and critical engagement with the dialogues of 2-year-olds in preschool 'mixed-age' settings can help teachers work more effectively with these learners. The teachers in our study carried out in-depth coding of, and reflection on, comprehensive video footage of dialogues involving 2-year-olds in two preschool settings over 2 years. In-depth analysis of the video footage enabled teachers to see 2-year-olds as more competent and complex learners than they had previously realised. Teachers also saw the important role that older peers played in the 2-year-olds' learning. Our findings provide insights into how teachers can adjust their own dialogues to encourage 2-year-olds to become agentic learners alongside their older preschool peers. Teachers in this project made significant shifts in their pedagogy, practice, and policy as a consequence of the discoveries they made through analysing the video footage of dialogues. They came to appreciate the multiple opportunities that exist for 2-year-olds to be leaders of their own learning in the preschool environment. These findings are important for teachers who work with 2-year-olds in mixed-age settings because they highlight previously overlooked, trivialised, or ignored dialogues as a central source of younger learners' agency, and provide new ways of engaging with these dialogues effectively. These discoveries challenge teachers to view 2-year-olds as unique personalities and fully contributing members of the preschool learning community. The discoveries about dialogue should inform pedagogy, assessment, and the kinds of genre that are granted legitimacy in the preschool. [This report was written with Shavaurn Bennett, Bev De Manser, Catherine Geddes, Caroline Hjorth and Annette Rogers.]