This paper brings together two research strands that rarely interact and might even seem in-commensurable, namely sociolinguistic approaches to linguistic fluidity and multi-competence on the one hand, and structural approaches to linguistic coherence and grammatical systems on the other hand. I show that we can reconcile insights from these two strands in a linguistic architecture that takes communicative situations as the core of linguistic systematicity, and integrates them into lexical representations. Under this view, communicative situations are the basis for linguistic coherence and grammatical systems, while languages can emerge as optional sociolinguistic indices.
