This book is about the complex balance between effectiveness of law enforcement, in bringing wrongdoers to justice, and ensuring fairness to a criminal defendant. From my experience as a criminal law practitioner, I was concerned and intrigued by a perception that these two objectives may be mutually exclusive. In particular, the book focuses on the significance of maintaining the balance between limiting and protecting the right to silence and the right against self-incrimination in transnational proceedings. This spotlight came about as the result of an initial comparison I undertook of coercive measures in Denmark and Australia, which revealed that the greatest divergence between the uses of such measures in the two systems was the manner in which the rules regulating the right to silence functioned in administrative investigations. In addition, while talking to criminal justice practitioners involved in transnational cases, I learned of the potential difficulties that may arise in relation to differing approaches to the right to silence, for example, when the investigative and prosecution authorities want to question a suspect abroad and must decide as to which state’s rules should apply. By ensuring there is a proper foundation of fair trial rights in the national systems, which accords with minimum standards under international human rights law, the admissibility of evidence across borders is maximised, leading to more effective criminal prosecutions.