My main research interest is in ethnic identity and interethnic relations. I focus on the nature of ethnic, religious and national identities, and their interrelationships. I am interested in the conditions under which these identities become less or more important and strong, as well as the conditions under which they are experienced as compatible or rather contradictory. In addition, I examine various consequences of these identities, including well-being, group evaluations, and collective behaviour. Furthermore, I focus on interethnic ideologies (i.c. multiculturalism and assimilationism) and the content of social identities in relation to intergroup attitudes.