Increasingly, teacher professional development initiatives include teacher learning communities as part of their overall strategy. How teachers’ interaction with one another contributes to the conditions for teacher learning and the collective reasoning and action that underpins their work is not well understood. To further understanding, this dissertation examined two teams of primary school teachers in Singapore schools in their designing, teaching, reflecting in the light of the students’ responses and redesigning in cycles of lesson study to effectively implement the English Language (EL) national curriculum. This process provided opportunities for the teachers to reflect as a group on their experience with the curriculum and its implementation, and in so doing, improved the learning outcomes of students. The study explored how teachers talk about EL teaching and learning in the context of lesson study teams, what constitutes teacher learning in community and the factors influencing the conditions for teachers learning together in the nested contexts of local schools. An interpretive qualitative study using a case study methodology was employed. Data collected include observations, semi-structured interviews and artefacts developed and utilised in the course of the lesson study inquiry. Findings support several conclusions that further the understanding of the processes, outcomes and conditions for teacher learning in lesson study. Firstly, teachers’ talk about practice is characterised by their collective reasoning and action that is cyclical, deliberated and shaped by different sources of knowledge and school-level factors at the different stages of the lesson study cycle. Secondly, teacher learning is constituted by an enriched understanding of teacher knowledge, shifts in teacher beliefs and the enactment of shared literacy practices. Finally, the conditions supporting teacher learning are shaped by an interplay of the teacher’s learning orientation and the school’s learning orientation that both enables and constrains teacher learning. The analysis contributes to a more nuanced understanding of the entry points for curriculum deliberation and the learning pathways situated in lesson study teams, with wider implications for considering the affordances and sustainability of lesson study. It supports the case for lesson study as a site for mentoring novice teachers when contextual conditions foster the development of teachers’ dispositions towards the critical inquiry of practice. The implications of the study point to the importance of the role of the knowledgeable others in re-orienting teacher talk to promote inquiry perspectives. Overall, the study furthers the understanding of an interconnected perspective of how teachers learn together in lesson study that factors in the consideration of the influences at the individual, team and school level which enable and/ or impede a broader consideration of practice and richer conditions for teacher learning and mentoring novice teachers.