As a complex and challenging field, often called a “mess”, extraterritorial jurisdiction is difficult to regulate under international law. It provides broad discretion for states within the existing international legal framework. From this, it follows that extraterritorial jurisdiction is ultimately a matter of appreciation and interpretation and also one in which states choose to participate. In this sense, studying extraterritorial jurisdiction from a national perspective is necessary, especially if the analysed states are not part of the Western world. This book, edited by Danielle Ireland-Piper, perfectly answers this demarche as it provides an insightful view of the law and practice of extraterritoriality in East Asia from the perspective of criminal law, specifically in China, Japan, and South Korea.

The authors provide a detailed historical background of the selected states. In the case of China, it is surprising to note that the historical notion of inherent higher authority in governance and the idea that humans have the freedom to act within the rules and constraints of a particular situation, premised in the Book of Changes from around 1045 BCE, are echoed in the current legal and political system, and thus influence China's approach to extraterritoriality. The Chinese Criminal Code endorses an extensive extraterritorial jurisdictional assertion based on the nationality principle (for more than 400 crimes), including the controversial “effects” doctrine and the passive nationality principle.

Another striking feature of this work is that it offers a balanced analysis of constitutional and criminal provisions and relevant case law. In addressing the question of extraterritorial criminal jurisdiction in Japan, Ireland-Piper and Machiko Kanetake underline that Japanese criminal law asserts extraterritorial jurisdiction in various ways and that judiciaries endorse the view that such extraterritorial competence is presumed. The authors aptly introduce the extensive interpretation of the territorial principle, described in Japan as “ubiquitous theory” (henzai setsu), which provides a flexible legal framework and is considered the starting point for understanding what constitutes “domestic” crimes.

Ireland-Piper and Heetae Bae report that South Korea follows a permissive approach to extraterritorial jurisdiction similar to China and Japan. Thus, it is unsurprising that its legal system provides extensive grounds for the extraterritorial criminal jurisdictional assertion, including those based on the active and passive nationality principle, protective principle jurisdiction, and universal jurisdiction.

The book concludes with some remarks on convergences and divergences in the subject of law and practice, and, notwithstanding the interesting discussion generated by the authors, some remarks are needed. In addition to an interconnected history, the selected states are currently important economic and political actors, facts which ultimately influence and explain their permissive approach to extraterritorial jurisdiction. It would have been beneficial if the authors had extended this study to a state from East Asia with a slightly different background. Moreover, adopting a broader approach to the subject, not limited to a specific field (criminal in this case), would have offered a more complete picture of extraterritoriality in East Asia. Overall, the book is a welcome addition to the existing scholarship, and apart from bringing a bit of clarity to this “messy” field, it also invites deeper academic inquiry into extraterritorial jurisdiction in international law from a national perspective.