This chapter discusses the contributions of the landmark trial of Liberian President Charles Taylor, the first African former head of State, to be tried and convicted by an international criminal tribunal in a contested proceeding. Taylor was convicted in April 2013 for his role in planning, aiding, and abetting war crimes, crimes against humanity, and other serious violations of international humanitarian law which occurred during the Sierra Leone Conflict. The chapter examines the controversies associated with former President Taylor’s prosecution and the novel arguments addressing the waiver of immunity by a tribunal that was treaty-based and not created using the Security Council’s Chapter VII powers. Taylor argued that he was entitled to immunity under international law because the Special Court was a domestic court. In addition to examining the caselaw of the International Court of Justice, on which the Special Court relied to find that Taylor was not immune from prosecution, the chapter continues to discuss the historical and symbolic implications of this major prosecution for international criminal law. Finally, the chapter examines how the Special Court Taylor immunity decision has impacted the current case law relating to immunities and prosecution of heads of State at the International Criminal Court.