Skip to Main Content

International Law: Treaties

This guide contains resources and guidance to help students find international legal materials.



Treaties are agreements between sovereign states governed by international law. They are sometimes also known as conventions, covenants, charters, protocols, pacts or accords. Treaties can be bilateral or multilateral.

Bilateral Treaties

These are treaties between two sovereign states. Bilateral treaties can be searched in participating countries' websites/ databases. They may also be found in the United Nations Treaties Collection (UNTC) website (assuming they were registered with the United Nations).

Multilateral Treaties

These are treaties between three or more sovereign states. Multilateral Treaties are generally registered with and published by the Secretariats of international organisations (such as the United Nations).

Recommended books

Vienna Convention on the Law of Treaties - A Commentary
On the Interpretation of Treaties
Treaty Interpretation and the Vienna Convention on the Law of Treaties - 30 Years On
The Decolonization of International Law: State Succession and the Law of Treaties
National Treaty Law and Practice
Commentary on the 1969 Vienna Convention on the Law of Treaties
Customary International Law and Treaties

How to search for treaties


Tip Icon

Official full-text version of treaties can be found in the websites of the body or the organisation which performs the role of the Secretariat for that treaty.

There are various collections, indexes and repositories where you can search for treaties. See the end of this page for a list.

When searching for treaties, you can follow this process as a general guideline:

  • Find the full-text of the treaty.
  • Determine its status - is it currently in force?
  • Identify the names of the sovereign states that are parties to the treaty.
  • Find if any of the parties made any reservations or objections to any particular section of the treaty.
  • Review the drafts (travaux préparatoires - preparatory works) to understand the context of the treaty and how it developed over time.
  • Look at the history of the treaty since inception to see if any subsequent amendments have been made.

Treaties can be searched in various online databases and repositories. You can also find the full text of some treaties in Lexis Advance and Westlaw.

United Nations treaties


Bilateral and multilateral treaties, agreements and conventions registered with the United Nations can be searched in the United Nations Treaty Collection (UNTC) website.

This website has 3 separate search interfaces, and they all serve slightly different purposes:

1. United Nations Treaty Series (UNTS) - contains all treaties and international agreements registered with the United Nations since 1945. You can search for the full text as they appeared in the volumes of the UNTS, as well as the texts of treaties yet to be published.

2. Status of Multilateral Treaties Deposited with the Secretary-General (MTDSG) - this section of the UNTC website (also known as the 'Depository') follows the chapter structure of the original publication. For each treaty, you can find information on ratification, accession, signature and texts of any declarations, reservations or objections submitted by parties.

3. League of Nations Treaty Series (LNTS) - this section of the UNTC website contains treaties registered with and published by the Secretariat of the League of Nations (5 July 1920 - 3 October 1948). The League of Nations was replaced by the United Nations after the Second World War, but (unless there is a specific reason) the treaties in the LNTS are normally still in force.

Research Guides on UN Treaties

See below for a list of research guides on finding UN treaties, developed by various law libraries and law research institutions around the world.

Explore them as they contain lots of additional information not covered in this guide.

Treaty research guides


These are research guides on finding treaties in general.

They are not specifically about finding UN treaties, but they do mention them.

Other treaty resources



European Union

South America

United Kingdom

United States

Other Useful Treaty Websites