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International Legal Research: Researching Treaties

This guide will serve a beginning set of resources for those legal researchers who are searching in the field of international law. It will focus on finding treaties and other international agreements.

Finding a non-US Treaty

United Nations Treaty Collection  
This collection includes:
                League of Nations Treaty Series (L.N.T.S.), 1920-1944
                Full-text of treaties registered with the Secretary of the League
                United Nations Treaty Series (U.N.T.S.), 1944-
This collection includes full-text of all bilateral and multilateral treaties registered with the Secretariat. Most comprehensive treaty series, but there can be time lags. 

Status of Treaties Where United States is Not a Party
Checking for signatories, status, ratification and reservation information on treaties where the United States is not a party can be difficult. There is no one collection of links providing access to all relevant treaty information.  

The United Nation’s Status of Multilateral Treaties Deposited with the Secretary-General is a good place to start but status information and reservations are limited to a small portion of the world’s treaties. Check databases or web sites provided by treaty secretaries and depositories for regional organizations.

Treaty Collections in Print

Sources for US Treaties

A publication of the Treaty Affairs Office at the U.S. Secretary of State, this is published annually by the Department of State to provide information on treaties and other international agreements to which the United States has become a party and which are carried on the records of the Department of State as of January 1st in its most recent publication year.

  • International Legal Materials (I.L.M.), 1962-

This journal published by the American Society of International Law includes full-text of selected treaties and agreements. It is available on LexisNexis, Westlaw and Hein Online (U.S. Treaties and Agreements Library).

LexisNexis and Westlaw have separate databases of U.S. treaties dating back to 1776 on LexisNexis and 1778 on Westlaw.

Websites to check

Web Sites of Regional Organizations for Treaties

Check organization web sites such as the Council of Europe, Organization of American States for text of treaties of their member states. Many IGO’s have web sites containing text of regional treaties.

EISIL: Regional Organizations 
Links to a variety of regional organizations, organized by continent and/or geographic area.  This is a good resource to identify those regional organizations that may not be listed below.

African Union (AU)

Official website of the African Union, a regional organization consisting of many African states.  This website includes the text and status of OAU/AU treaties.  In addition it provides court decisions as well as current news about the AU.  

Europa -- Website of the European Union
Official website of the European Union, a regional organization of some European nations that has some political authority over member nations.  Information and documents include current news, official documents, reports, statistics, treaties, and other publications.  

Association of Southeast Asian Nations (ASEAN)

Official website of ASEAN, a regional organization for ten Southeast Asian nations.  Contains basic information about ASEAN’s history and development in the region.  In addition it also includes various publications such as statistical publications, reports, the ASEAN charter, and documents about the ASEAN Secretariat.  

Organization of American States (OAS)
Official website of the Organization of American States, a regional organization which includes all 35 independent states of North and South America. Contains information and documents about the OAS, including charters, declarations, reports, treaties, and other legal documents.