The title of my research is " The Collaboration of States and the International Criminal Court in Fighting International Crimes." Its aim is to figure out how the International Criminal Court (ICC) (which is going to be set up within a few years) and the courts in States can work together in order to make more effective system to bring justice to the international criminals. Historically, the international criminals were tried by the states' courts and not by the international institutions. Therefore, to accommodate the jurisdiction over international crimes to the ICC may cause some frictions between the ICC and the states. The objections raised by the United States to the ICC Statute are good examples of this friction. My project tries to elaborate the legal framework to settle the conflict between the states and the ICC. By doing so, I would like to contribute to the development of better system of international criminal justice.