Critical Participatory Action Research (CPAR) requires communicative space to develop shared understandings and decisions. We examine the interactional accomplishment of such a space between a classroom practitioner and an academic researcher when meeting to reflect on a lesson and agree on future action to bring about change in the practitioner's classroom practice. Conversation analysis of an audio recording of the meeting establishes how advice giving emerged and was managed as a delicate matter that required achieving shared understandings of what actually happened in the lesson, what could have happened, and what should happen in future lessons. Findings provide insights into how participants used reported and hypothetical speech to manage advice and reach agreement, produce and maintain intersubjectivity through interaction, and address epistemic asymmetry related to the differing experiences and roles that they brought to the action research study. Overall, the article contributes understandings of the ways that interactions produce communicative space in CPAR.