The study provides a practicable solution to the question whether and how witnesses can be prepared for their testimony before the International Criminal Court (ICC). For that purpose, the book highlights and analyses relevant judicial decisions of international tribunals as well as selected domestic decisions, especially from the USA and UK. It establishes an interdisciplinary approach by paying much needed attention to psychological pitfalls that arise from the interrogation setting of witness preparation sessions. Finally, the study concludes with a draft rule for ICC witness preparation. Thus, it is of interest to scholars and practitioners of international criminal law alike.