Researching international treaties (a type of binding international instrument) and other international agreements can be a complex process. There are, however, many useful guides available to provide assistance with this type of research. Note that treaties/international agreements can be bilateral (between two parties) or multilateral (between three or more parties).
Links to some of the major MEAs (multilateral environmental agreements) are listed at right.
The following books serve as introductory works to treaties:
Modern Treaty Law and Practice by 
On the Interpretation of Treaties by 
The Oxford Guide to Treaties by In the U.S., treaties are those international agreements that are made with the advice and consent of the Senate. International agreements not submitted to the Senate for approval are called executive agreements. Under the Case-Zablocki Act (1 U.S.C. § 112b), the U.S. Secretary of State must transmit to Congress the texts of any agreements to which the U.S. is a party (other than treaties) within 60 days of their entry into force.
The following are electronic guides to researching treaties:
See the list below for access to various collections of international environmental treaties and agreements.
Treaties in Force (TIF) lists U.S. treaties and agreements still in force, organized by country and subject. TIF is published annually and is available on the U.S. State Department's website. References to the texts of the treaties are also listed, if available. U.S. treaties first appear as a single document with a Treaties and Other International Acts Series (T.I.A.S) number. They are then compiled in United States Treaties and Other International Agreements (U.S.T.). Both of the aforementioned publications are no longer published in print, and they are available in PDF format in HeinOnline's Treaties and Agreements Library. Westlaw and LexisNexis also contain U.S. treaties and agreements, and the U.S. State Department's website also provides access to T.I.A.S. from 1981 to 2020. U.S. treaties from 1776-1949 are available in digitized format via the Law Library of Congress website. For more in-depth information on researching U.S. treaties, see one of the research guides listed above.
The travaux préparatoires are the documents created during the negotiations, preliminary discussions, and drafting of an international agreement. For assistance researching travaux préparatoires, see the following guide posted on GlobaLex.
The UN Treaty Series (U.N.T.S.) is a collection of treaties and other international agreements, published since 1946, per Article 102 of the UN Charter. U.N.T.S. is available in electronic format (PDF). Click on "Advanced Search," then "Search For" treaty, and then filter by volume number.
