The diffusion of innovation is critical to societal progression. In the field of education, such diffusion takes on added significance because of the many stakeholders and accountabilities involved. This article presents the argument that efforts at diffusion which are designed from a top-down perspective are not sustainable over the long term because such a perspective does not sufficiently acknowledge the importance of tacit knowledge in the successful adoption and adaptation of innovations. Using examples drawn from the trialing and implementation of a suite of research innovations in the Singapore education system, the argument is made that tacit understandings of any given innovation are attained through dialogue and embodied practice within authentic contexts, and that these very contexts and opportunities for dialogue are precisely the affordances of Communities of Practice. The article draws some tentative conclusions about systems-level moves and strategies which might nurture the dialectic of theory, practice, and epistemology by leveraging existing social structures. (Contains 2 tables.)