This book provides a comprehensive analysis of the content, scope, and function of due diligence across various areas of international law. Looking at current tendancies towards proceduralisation and more proactive risk management, it reveals the promises and limits of due diligence as a concept for enhancing accountability and compliance.

Due Diligence in International Law identifies due diligence as the missing link between state responsibility and international liability. Acknowledged in all legal fields, it ensures international peaceful cooperation and prevents significant transboundary harm, yet it has thus far not been comprehensively discussed in literature. The present volume fills this void. Kulesza identifies due diligence as a principle of international law and traces its evolution throughout centuries. The no-harm principle, key to identifying responsibility for transboundary harm, focal to international environmental law and applicable to e.g. combating terrorism, follows states’ obligation of due diligence in preventing foreign harm. This obligation, present in various treaty-based and customary regimes is argued to be a principle of international public law applicable to all obligations of conduct.

With the importance of non-State actors ever increasing, the traditional State-centric approach of international law is being put to the test. In particular, significant accountability lacunae have emerged in the field of human rights protection. To address these challenges, this book makes a case for extraterritorial due diligence obligations of States in international human rights law. It traces back how due diligence obligations evolved on the international plane and develops a general analytical framework making the broad and vague notion of due diligence more approachable. The framework is applied to different fields of international law which provides guidance on how due diligence obligations can be better conceptualized. Drawing inspiration from these developments, the book analyses how extraterritorial human rights due diligence obligations could operate in practice and foster global human rights protection.

Due diligence obligations are typically described by scholars and practitioners as 'elusive', 'weak', and difficult to pin down in the abstract. Challenging these assumptions, this book offers a systematic reconstruction of the foundations of due diligence obligations of states and explores their nature, rationale, content and scope of operation in international law. Tackling due diligence from a general perspective, this book seeks to complement scholarly studies on public international law obligations and their theory. This book will be relevant for academics, practitioners, graduate students across international law and anyone seeking to better conceptualise due diligence under international law and understand how due diligence obligations are operationalised in practice.

This perceptive book analyzes the scope of the duty to prevent genocide of China, France, Russia, the UK, and the US in light of the due diligence standard under conventional, customary, and peremptory international law. It expounds the positive obligations of these five states to act both within and without the Security Council context to prevent or suppress an imminent or ongoing genocide.

This book offers a comprehensive overview of the international law applicable to cyber operations. It is grounded in international law, but is also of interest for non-legal researchers, notably in political science and computer science. Outside academia, it will appeal to legal advisors, policymakers, and military organisations.

Tallinn Manual 2.0 expands on the highly influential first edition by extending its coverage of the international law governing cyber operations to peacetime legal regimes. The product of a three-year follow-on project by a new group of twenty renowned international law experts, it addresses such topics as sovereignty, state responsibility, human rights, and the law of air, space, and the sea. Tallinn Manual 2.0 identifies 154 'black letter' rules governing cyber operations and provides extensive commentary on each rule. Although Tallinn Manual 2.0 represents the views of the experts in their personal capacity, the project benefitted from the unofficial input of many states and over fifty peer reviewers.