This empirical study investigates the existence of a hypothetical regional standard for Spanish in Catalonia based on a corpus made up of transcripts of some 70 hours of recorded interview material. The determining factors in the development of linguistic norms are analyzed in terms of the frequency of usage and the formal and informal acceptability of some 80 linguistic phenomena. The qualitative and quantitative analyses are supplemented by a study of the metalinguistic information and the linguistic attitudes identifiable in the interviews.