This paper brings an International Criminal Law perspective to the conference and explores a topic of importance in the Middle East: the alleged commission of international crimes by Bashar al-Assad, President of Syria, and Abu Bakr al-Baghdadi, leader of the Islamic State. This paper answers these questions: Were international crimes committed within the conflicts in Syria/Islamic State/Iraq? Are the leaders of Syria and the Islamic State implicated? Is there a path for prosecuting these crimes in the International Criminal Court (ICC)? The thesis of this paper is: International crimes were committed in the Syria/Islamic State/Iraq theater and the leaders of Syria and the Islamic State are implicated. Furthermore, it is possible for the ICC to acquire jurisdiction. While neither Syria nor the Islamic State (as a State) are parties to the Statute of Rome, this paper will explore avenues for holding the two leaders accountable for the alleged crimes. (The paper also addresses the dichotomy of international v. non-international conflict.) The basis of prosecution rests on three of the four types of crimes included in the Statute of Rome: Crimes Against Humanity, War Crimes, and Genocide. The elements of these crimes will be applied to events in the theater and the level of responsibility of the two leaders will be determined. In the case of the Islamic State, the focus will initially be on Crimes Against Humanity, especially extermination and sexual slavery. Additionally, if one is to assume that ISIS did in fact constitute a State as outlined by the 1933 Treaty of Montevideo, charges of War Crimes might also be leveled, to include attacking civilians, attacking civilian objects, rape, and sexual slavery. Finally, the question of charges of the crime of Genocide will also be considered. In the case of Syria, it is possible to consider Crimes against Humanity and War Crimes. In the former, murder and other inhumane acts serve as the basis prosecution. In the latter, the crimes of willful killing, destruction and appropriation of property, attacking of civilians, excessive incidental death, injury, or damage, killing or wounding a person hors de combat, murder, attacking civilians, and cruel treatment. Sources will include international conventions and customary law, jurisprudence from the international courts and ad hoc tribunals, accounts and reports of potential and alleged crimes, and journal articles as accepted by legal scholars.