Skip to Main Content

International Law Research Guide: International Treaties

A research guide to help researchers locate and understand public and private international law resources.

The International Treaties tab is currently being updated.  Check back soon for updated links and content below.  (1/23/2023)


Treaties (also called covenants, protocols, acquis, conventions, pacts or charters) are international agreements between states and/or international organizations. Treaties are primary sources of international law. For a guide to finding treaties, click here. Conventional international law is based on consent of state parties and as such the treaty applies only between those parties. In determining treaty application, watch for state party reservations, understandings and declarations which can transform that state's obligations. Treaties only bind nonparties when they form the basis for customary international law. Customary International Law is formed when states consistently act in a certain way (state practice) out of a sense of legal obligation (opinio juris). State practice includes domestic legislation, regulations, treaties, judicial decisions, diplomatic communications, NGO and IGO practice (for example General Assembly Resolutions and state voting practice). Look at judicial decisions and executive communications for evidence of opinio juris. A state may escape the application of customary international law by being a persistent objector.

Some treaty databases available on LexisNexis:

Some treaty databases available on Westlaw:

  • US Treaties and Other International Agreements - Complete full-text coverage of international and Native American treaties to which the United States is a party from 1778 to present.
  • United Kingdom Human Rights International Treaties - Treaties from 1950 to current.
  • European Union Treaties - Text of treaties between member states of the European Union, including the founding treaties establishing the European Coal and Steel Community (1951), the European Economic Community (1957), and the European Atomic Energy Community (1957); accession documents that enlarged the European communities; treaties of amendment such as the Single European Act (1986); and the Treaty of European Union (Maastricht Treaty, 1992).
  • Also available through browsing: Content Types - Specialty areas > International Materials

Paper Sources for Major Treaties

Links to Fundamental Treaties

Online Sources for Major Treaties

The websites of major international bodies often display their founding treaties:

Important Treaty Information to Consider

  • Text of the treaty or agreement
  • Parties to the agreements (multilateral or bilateral)
  • Effective dates
  • Status and ratification information
  • Reservations or declarations
  • Modifications/updates to the treaty
  • Domestic implementing legislation

Finding A Treaty in Official Publications

  • Different from country to country (Published in various sources)
  • Official gazettes (ex: Bundesgesetzblatt, Part II for Germany)
  • Country treaty series (Example: United Kingdom Treaty Series)
  • Statutory compilations (ex: U.S. Statutes at Large)
  • League of Nations / United Nations Treaty Series (L.N.T.S. / U.N.T.S.)
  • International Legal Materials (I.L.M.) (recent vols on WL/LX)
  • Regional organizations (Council of Europe, OAS)

Other Sources of Treaties

Treaty Analysis, Commentary, and Interpretation