This study describes teachers' experiences in a preschool professional learning community (PLC) in order to gain understanding of the role of documentation in group learning. A central underlying assumption of PLCs is that teacher learning involves talking with colleagues about teaching and grappling with the issues embodied in everyday classroom life. We utilized a qualitative case study design in order to emphasize the situated and contextual nature of teachers' professional learning in context. Data sources included the following: observations of PLC sessions, interviews with participating teachers, and the classroom documentation teachers shared during the sessions. We found that the incorporation of documentation in the PLC made implicit assumptions about children visible in order to be scrutinized. In addition, the teachers' reflections on the documentation highlighted conflicting notions about teaching as either technical practice or inquiry. In contrast to traditional delivery approaches to teacher learning, we argue that PLCs focused on documentation encourage teachers to problematize practice rather than simplify it. The process of reflecting on children's work made shifts in thinking about the nature of teaching possible.