EN
This paper addresses the legitimacy issue of transnational non-governmental organizations. The sources of legitimacy are identified and analyzed and the focus is given on those which are most frequently used by transnational non-governmental organizations. Arguments and counterarguments which dispute this legitimacy are also identified. Emphasis is given on the discrepancy of social and normative concept of transnational nongovernmental organizations legitimacy, because the tendency to consider them under the legitimacy of liberal democratic states as constitutionally defined institutions still persists.