This article focuses on the practical sense of ethnicity as a constitutive element of ethnocultural identities. Building on the sociology of Pierre Bourdieu, we claim that it is essential to reflect how the practical sense of ethnicity contributes to the social reality of ethnocultural identities, how social actors practical knowledge about ethnicity contributes to their ethnocultural identity. While it seems that the processes of forming ethnocultural identity are usually associated primarily with minorities, we point out that in order to analyze the formation of minority ethnocultural identities it is always necessary also to speak about the formation of dominant ethnocultural identities. The complex relationships among various ethnocultural identities constitute the "field of ethnicity". As an instrument of social orientation in this field, the sense of ethnicity is not merely a sense of ethnocultural difference, it is a sense of ethnocultural distinction. Political strategies of social inclusion through integrating minority ethnocultural identities inevitably modify the whole structure of the field of ethnicity. The sense of ethnicity dominating Czech society until recently, which perceives minorities as ethnocultural collectivities and conceives the cultural diversity of Czech society in the form of ethnocultural diversity leads to an ethnocultural delimitation of the Czech national identity. By treating the Czech national identity as a dominant ethnocultural identity, all other ethnocultural identities are, as an unintended consequence of this form of social inclusion, excluded from the imagined ethnocultural community of the Czech nation. The question is whether the dominant institutions and discourses will privilege the sense of ethnicity over other social identities.