The authors assess the theoretical and methodological problems arising in the definition and in the study of ethnic conflicts in the contemporary transforming world order, and give their definition of ethnic (ethnopolitical) conflict with a focus on the political mobilization of ethnic identity. Building on a qualitative analysis of 27 cases of ethnic contention in different countries and regions of the world chosen by expert evaluation, they elaborate an analytical model for studying ethnic conflict using a factor-based approach. The key factors that drive ethnic contention are detected, considered and compared: these include collective memory and claims for language and cultural autonomy, religious and confessional differences, economic and social disparities, clan and tribal interests overruling the common interest, as well as external influence and the political accommodation of ethnic interests. The comparative study brings to light, as the article arguments, three types of ethnic conflict: territorial, institutional and policy-oriented. Three cases are presented to illustrate these findings, with special attention to contention in the post-Soviet political space. The study brings forward arguments to support middle range theory: it can be adapted to evaluate ethnic conflict as a driver of political change in the contemporary world, whereas “grand theory” has in this case considerable limitations which are due both to the complex nature of these conflicts and of the transformations of the world order, and to the highly contested contemporary theoretical discourse on conflict and ethnicity. This does not, however, overrule prospects for further steps towards elaborating a broad theoretical framework for conflict assessment and regulation. The authors see the transformation of identity conflicts into conflicts of interests and the formation of appropriate institutions for their reconciliation as an effective instrument for incorporating ethnic identities into the identity politics agenda on the national level. Depoliticizing ethnicity is a marker of effective conflict regulation and prevention. This can be achieved by promoting public policies in the social sphere, with special attention to education, and by a positive convergence of civic and ethnic identities over a national “accord on development”. To achieve a positive outcome, it has to be sustained by thriving community activities in various spheres where different identities meet.