In a globalising world, collaboration in multicultural teams (MCTs) has become crucial for the success of the organisations. In this paper, we study how these MCTs, despite cultural and linguistic differences, can produce positive dynamics and outcomes. Aim is to develop hypotheses and a conceptual model of team effectiveness in MCTs, thus providing the basis for our future empirical analysis. We investigate the links between common in-group identity, cultural intelligence, communication and team effectiveness in MCTs. We contribute to the research field in three ways. Firstly, we propose an integrative model which encompasses key factors of team effectiveness in MCTs. Secondly, unlike previous research, we study cross-cultural interactions at team rather than individual level. Thirdly, building on social identity and self-categorisation theories, we apply the construct of common in-group identity to MCTs, which remains an underexplored approach to date.