In multi-ethnic contexts, it is not uncommon to find that dementia carers or their clients are using, as the medium for communication in care, a language in which they are not comfortable and/or are not fluent. In extreme cases, there could be no shared linguistic code at all. This article asks how feasible it is to provide adequate care with inadequate mutual language knowledge. In particular, it challenges the claims of some care-providers that nonverbal communication is a legitimate substitute for linguistic interaction. With reference to two recent models of aspects of communication, the article offers new insights into the necessary parameters for effective interaction. The conclusions have important implications for future decisions in dementia care. Meanwhile, the account extends the boundaries of "language awareness" by demonstrating the social importance of developing insights into linguistic practices in challenging contexts.