In this article we propose to show how interactionally based conversation analysis can con tribute to understanding the sociolinguistic realities of the Catalan situation. Building on existing studies, and in the light of questions which we formulated some years ago, we will consider the current validity and variation of norms of language use, and other phenomema arising from intetaction in Catalan-Castilian contact situations. To conclude we will present a framework within which diHerent types of conversation occurring in contemporary Catalonia can be situated, according to language choice and the language behaviour of speakers.