International law books cover the rules, norms and principles that guide relations between sovereign states. Here we gathered 23 free titles in PDF that walk you through this field from foundations to specialized areas.
The collection covers public international law, humanitarian law, human rights, environmental law, criminal law and private international law. Topics range from sources and state jurisdiction to customary international law, treaties, armed conflict, and conflict-of-laws across borders.
Every book is a free, legal PDF from UN agencies, ICRC, OHCHR and academic institutions. No signup or email needed: pick your section and start reading.
Foundations
Books on Public International Law
These titles cover the foundations: sources of international law, state jurisdiction, customary international law, treaties, and the role of the United Nations. Start here if you want a broad map of the field.
Volume one of the United Nations Office of Legal Affairs handbook compiles foundational instruments: the UN Charter, the Statute of the International Court of Justice, and core declarations on sovereignty, decolonization and statehood. The reference for primary sources of public international law.
Volume two of the United Nations handbook gathers the core treaties on the law of armed conflict, international criminal law, and disarmament and non-proliferation. Includes Geneva Conventions, the Rome Statute, and key arms control conventions.
Volume three of the United Nations handbook compiles instruments on the law of the sea, international environmental law, and international watercourses. Reference for UNCLOS, MARPOL, biodiversity treaties and shared water resources.
Volume four of the United Nations handbook gathers instruments on international labour law, the law of cultural relations, and international trade and investment law. Includes ILO conventions, UNESCO instruments, and core trade and investment treaties.
A 353-page benchbook from the American Society of International Law that walks judges through how international law operates in U.S. courts. Covers sources, jurisdiction, treaties, customary law, immunities and the use of foreign and international authorities.
An accessible glossary-style introduction by the Swiss Federal Department of Foreign Affairs. Defines core international law concepts in plain language: sources, treaties, jurisdiction, state responsibility, sanctions and dispute settlement.
A research guide from the American Society of International Law that maps how to find primary and secondary sources of public international law. Covers treaties, customary law, judicial decisions, soft law, and key institutional databases.
An Emirates Center lecture by Christoph Schreuer that maps the formal sources of international law: treaties, custom, general principles, judicial decisions and writings of publicists. Concise, authoritative, and grounded in ICJ practice.
A book chapter by Marks, Rudolf, De Feyter and Schrijver on the role of international law in implementing the right to development. Examines treaty obligations, the work of UN human rights bodies, and the political tensions around a binding development convention.
Lecture notes by M. S. Rama Rao that introduce public international law in plain language. Covers state sovereignty, sources of law, recognition, treaties, and the basics of jurisdiction and the law of war.
A short overview by Robert Beckman and Dagmar Butte that summarizes the structure of the international legal system in 12 pages. Defines international legal personality, sources of law, jurisdiction and the basics of treaty interpretation.
International humanitarian law (IHL) regulates armed conflict and protects those who do not take part in hostilities. The texts below cover the Geneva Conventions, ICRC doctrine, and the law of armed conflict.
Co-published by the Inter-Parliamentary Union and the ICRC, this 132-page handbook explains international humanitarian law through clear Q&A: what IHL is, when it applies, who it protects, and how parliamentarians can implement Geneva Convention obligations in national legislation.
A Peace Operations Training Institute course by Antoine Bouvier on international humanitarian law and the law of armed conflict. Covers the Geneva Conventions, distinction, proportionality, and how IHL applies in practice during peace operations.
A specialized 360-page study by Hausler, Urban and McCorquodale on how international humanitarian and human rights law protect education during armed conflict. Covers students, teachers, school facilities and remedies, with treaty appendices and case analyses.
Kristin Hausler, Nicole Urban, Robert McCorquodale
These resources walk through the international human rights system, including its treaties, monitoring bodies and enforcement mechanisms. Use them to understand how rights are protected across jurisdictions.
A 237-page handbook co-published by the Inter-Parliamentary Union and the United Nations Office of the High Commissioner for Human Rights. Explains what human rights are, how international human rights law works, the role of state sovereignty, and how parliamentarians can implement human rights obligations in national legislation.
An OHCHR handbook that introduces United Nations staff to international human rights law. Covers the scope of human rights, state responsibility, the difference between human rights law and humanitarian law, and the main international human rights instruments.
A USCIS Officer Training module on international human rights law. Covers the sources of international law, how human rights instruments operate, and how rights apply in refugee, asylum and protection adjudications.
These books map the treaties, principles and institutions that govern environmental cooperation between states. Topics span climate change, biodiversity, marine protection and pollution control.
Course materials prepared by Professor Daniel Bodansky for the United Nations Office of Legal Affairs. Compiles the foundational treaties of international environmental law alongside Bodansky lectures on sources, principles, climate, biodiversity and watercourses.
Drawn from UNEP publications, this handbook explains the framework of multilateral environmental agreements and how states implement them. Covers compliance, enforcement, judicial handling of environmental cases, and negotiator practices.
International criminal law deals with individual criminal responsibility for the gravest crimes: genocide, crimes against humanity, war crimes and aggression. These books cover doctrine, the ICC, and landmark cases.
Course materials prepared by Judge Kevin Riordan for the United Nations Office of Legal Affairs. Compiles the foundational instruments of international criminal law: the Genocide Convention, the Convention against Torture, the Rome Statute, and the rules of procedure and evidence of the ICC.
Practitioner training materials developed for the OSCE-ODIHR, ICTY and UNICRI project on transferring war crimes case knowledge to national jurisdictions. Covers the scope of international criminal law, general principles, courts, genocide, crimes against humanity and war crimes.
A working paper from the Iraq Legal Education Initiative at Stanford Law School. Walks readers through the foundations of international criminal law: individual criminal responsibility, core crimes, jurisdiction of international tribunals, and the Rome Statute regime.
Private international law, also called conflict of laws, decides which jurisdiction applies when a legal dispute crosses borders. The books below cover contracts, family, property and judgments.
An ASIL electronic resource guide by Don Ford on private international law. Maps the field across international sales, commercial arbitration, regional harmonization, and online research databases.
An article by David P. Stewart on the evolving definition of private international law and its expanding scope. Examines conflict-of-laws doctrine, jurisdictional rules, and the enforcement of foreign judgments across legal traditions.
This is the full lineup of free international law books in our library. Bookmark the page if you study or research the field, since we add new titles every month.
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