In this paper we present a dialogue model which has as its main goat to place in context the utterance generated by the speaker. The dialogue model considers that an intervention generates one or more ilocutive acts which are handled as flmctions. These functions subcategorize to or are subcategorized by other functions in the dialogue. The model uses an exchange schema with the purpose of expressing the different ftmctional subcategorizations. These schemas have properties close to the semantic forms of the verbs in a lexicalfunctional context.