The present paper discusses the issue of attaining shared knowledge in and by interpreter-mediated interaction, with particular focus on the role of the dialogue interpreter in this process. The dialogue interpreter (Swedish ‘dialogtolk’ or ‘kontakttolk’) acts within the Swedish social welfare system. Since the end of the sixties there have been dialogue interpreters working at institutions such as police stations, social welfare centers, hospitals and courts. They provide an interesting service for laymen and officials speaking in different languages.