The significant contribution dialogic engagement makes to children’s development is widely documented (Alexander, 2018; Wells, 2007). Its place in classroom discourse is also accepted with teachers playing a central role in supporting its advancement (Michaels & O’Connor, 2015). It is agreed that without their support, children would be unable to sustain this type of engagement. There is, however, limited information available regarding the approaches taken by teachers in lower primary classrooms in Ireland, to support the development of dialogue with and amongst their children. This study, in its adoption of Vygotsky’s (1986) socio-cultural theory of learning, sought first to identify teachers’ knowledge and practice with regard to developing dialogue with and amongst their children. Secondly, it examined how participation in a professional learning community (PLC) could facilitate teachers in reflecting on and advancing their knowledge and practice in this area. This study operated within a subjective paradigm that celebrates the complexities of human engagement. Data gathered from interviews, observations, recordings of meetings and audio/audio-visual recordings of practice served to create a case study that featured the experiences of nine teachers in two schools over the course of one academic year. A PLC was established in each school and over six cycles of engagement teachers were facilitated by the researcher in examining their knowledge and practice.Inductive and deductive analysis of the study’s data revealed that while initially teachers were unsure about how to develop dialogue amongst their children, their knowledge and practice was positively impacted by their participation in a PLC. The study’s findings suggest that adopting a speculative stance assisted teachers and children in their endeavours to engage dialogically. With regard to teachers’ professional learning, it appears that the facilitation available within the PLC may have been insufficient to bring about changes in practice, and it may have been the opportunity to avail of coaching that assisted participants in reflecting on and altering their practice. Recommendations arising from this study include the need for further investigation regarding the place of dialogic engagement in lower primary classrooms, and the investment in a cohort of teachers within schools who will nurture inquiry through dialogue and facilitate reflective practice.