While teacher learning has become a locus of school reform across many international settings, there is relatively little examination of the idiosyncratic ways in which policy discourses on teacher learning are enacted in schools. In this paper, we aim to investigate how these policy discourses are translated and configured into practices and thus, enacted into concrete realities. Using the conceptual notion of "multiple ontologies," we argue that teacher learning is actualized in a multiplicity of socio-material entanglements, not as a single reality, but as a multiplicity of realities that coexist, simultaneously, in the mesh of assemblages that we call "school." In this study, we describe and trace how particular socio-material configurations of teacher learning produce concrete realities of practice that mobilize and generate specific networked effects. We conclude that the postulation of multiple ontologies of teacher learning prompts a shift in how policy makers could conceive of and develop strategies aimed at transforming teaching practices.