The prevention of armed conflicts is stated as the priority policy of various international organizations, among which the EU and the OSCE. Based on the semi-structured interviews with high bureaucrats and civilian experts, who are engaged in conflict prevention policies within the two international organizations, the article compares the development and implementation of EU and OSCE strategies to prevent armed conflicts. With the support of the second method, the analysis of primary and secondary sources regarding the prevention of armed conflicts (legal acts, e. g. declarations, resolutions, action-plans and other documents the EU and the OSCE have adopted), the author tries to answer the research questions through three domains: (1) what are the connecting points between the conflict prevention policies led by the EU and those led by the OSCE ; (2) what are the differences among them; and (3) what are the lessons learned/good practices and what could be done in order to make the EU and the OSCE (as well as other subjects of international relations) more effective in preventive action. The analysis has shown both international organizations rely mostly on “structural” (long-term) prevention, meanwhile they lack the capacities to enforce hard(er) power. However, each of them has a set of comparative advantages that can be maximized only if the coordination and cooperation among them (and other subjects of international relations) improve. The major obstacle for more effective prevention is the lack of political will, and not the lack of capacities/resources. Therefore, the only way forward is to promote the concept of conflict prevention on all levels of international relations, aiming towards turning it into a norm in international relations (and not “a noble idea“ of lonely Don-Quixotes only, as it is today).