State immunity protects the world''s most powerful individuals from prosecution in foreign states,no matter how serious the alleged crime. This book clearly explains which individuals are immune, for what conduct and for what period. The justifications for immunity are examined and state practice, including the decisions in the Pinochet case, are analysed. This book shows that immunity is only narrowly available to the highest of state officials whilst in office, and that the immunity accorded, by consent, to special missions is otherwise sufficient. This book argues that former high state officials are not immune from prosecution for serious offences committed on the territory of other states. The analysis demonstrates that not all official conduct automatically imparts immunity from prosecution. The development of the regime for the prosecution and punishment of international crimes by international courts is considered and the perceived conflict between immunity and impunity is examined in the light of the complementarity principle of the International Criminal Court. This book is essential reading for all international lawyers, academics and students.