Whereas in Chapter 8 we focused on the effects of a bilingual experience on social psychological mechanisms relevant to language behaviour, in the present chapter we discuss the result of the interplay of these mechanisms with language behaviour in situations of interpersonal interaction. In order to understand interpersonal communication in an intercultural context one has to understand how meaning is negotiated when the interlocutors are members of different ethnolinguistic groups; how language interacts with processes of social-cognition mediation; and thus how language may become a salient dimension of this interaction (Gudykunst, 1986). In intercultural communication people interact with one another both as individuals and as members of different social groups; social encounters are thus determined by interpersonal as well as by intergroup factors (Tajfel & Turner, 1979), and can be analysed along these two dimensions (Stephenson, 1981).

When two members from different cultural and ethnolinguistic groups communicate with one another, social categorisation occurs in such a way that people have a tendency to exaggerate differences on critical dimensions between categories and minimise differences within a social category (Tajfel, 1981). Social, cultural or ethnolinguistic groups are perceived as more distinct from each other if they differ on a large number of distinctive features, such as language, race characteristics, religion and social status (as, for example, in an encounter between an Anglo-Celt and an Indian from South India) than if they differ on one or two characteristics only (as would be the case in an encounter between a Briton and an Anglo-Celtic Australian). Furthermore, social categorisation produces ingroup bias which is based on ethnocentrism, that is, on the perception of one's own ethnic group as being superior to an outgroup.