The paper argues that ethnolinguistic vitality depends on four crucial social psychological factors: perceived strength differential, intergroup distance, utilitarianism and intergroup discordance. The influence of these factors on the vitality of subordinate and dominant groups is outlined. It is proposed that the vitality of both types of groups could be measured on the same scale. The low end of this scale indicates group members' disposition to dissociate themselves from the in-group's cultural values and practices. The high end indicates a perception of cultural distinctiveness, superiority, closedness and derogation of out-groups, i.e. high level of ethnocentrism. A theoretical model is proposed explicating how the interaction of vitality profiles of the dominant and subordinate groups leads to different acculturation orientations of subordinate groups (assimilation, integration, segregation, or marginalisation).