Journal of Conflict & Security Law C  Oxford University Press 2009; all rights reserved. For permissions, please e-mail: journals.permissions@oxfordjournals.org doi:10.1093/jcsl/krp008 ..................................................................................... The Definition of the Crime of Aggression for the Purpose of the International Criminal Court: Problems and Perspectives Sergey Sayapin ∗ Abstract The definition of the crime of aggression for the purpose of the Rome Statute of the International Criminal Court (ICC) remains a key issue of contemporary in- ternational criminal law. The work accomplished to date by the Preparatory Com- mission for the ICC and the Special Working Group on the Crime of Aggression has resulted in promising draft amendments to the Rome Statute, which defines the crime on the basis of relevant international law sources and suggests workable mechanisms of interaction between the Court and the United Nations Security Council. This article examines the draft amendments in a critical way and rec- ommends substantial and procedural improvements. In particular, the respective roles of the International Court of Justice and the United Nations General As- sembly for the determination of acts of aggression are reconsidered, and a more ‘measurable’ definition of the crime of aggression is proposed. It is suggested that the new rules of the Rome Statute, if duly recognized, should affect the practice of both the International Criminal Court and the Security Council, as well as of other relevant principal organs of the United Nations, such as the International Court of Justice. 1. Introduction It is an irony that now, sixty-three years after the establishment of the United Na- tions, a key concept of its Charter has still not been defined as a matter of binding international law. It is a declared purpose of the United Nations to ‘take effec- tive ... measures ... for the suppression of acts of aggression or other breaches of * Sergey Sayapin graduated from the University of World Economy and Diplomacy’s International Law Department (Tashkent, Uzbekistan), in 1999. In 2001, he received an LL.M. in International Human Rights Law from the University of Essex (Colchester, UK). He is currently Dr. iur. candidate at the Humboldt University of Berlin’s Chair for German and International Criminal Law, Criminal Procedure and Contemporary Legal History. This article reflects the views of the author alone and is not necessarily representative of those of any other institution or agency the author was in the past, or is currently, associated with. The author thanks Andrew Bell and Pierre-Emmanuel Ducruet, staff members of the International Committee of the Red Cross, Sevil Velieva, an LL.M candidate at the University of Essex, and two anonymous reviewers at the Journal of Conflict and Security Law, for their helpful opinions on the text, and invites readers to send their comments on this article to: sergey.sayapin@yahoo.com. .................................................................................................... Journal of Conflict & Security Law (2009) Journal of Conflict and Security Law Advance Access published March 27, 2009