Treaty law governs the creation, interpretation, application and termination of international agreements. Treaties are a central source of international obligations because they allow States and other recognised international actors to establish legal commitments.
PUBLIC LEGAL REFERENCE
Law of Treaties
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A treaty is an international agreement concluded between States or other recognised international legal actors and governed by international law. Treaties may create rights, duties and legal procedures for the parties that consent to be bound.
A fundamental principle of treaty law is that States are bound by treaties through their consent. Consent may be expressed through signature, ratification, acceptance, approval or accession depending on the agreement.
The Vienna Convention on the Law of Treaties 1969 provides widely recognised rules concerning treaty formation, interpretation, application and termination. It is a key reference instrument for studying treaty law.
Treaties are interpreted according to international legal rules, including the ordinary meaning of treaty terms, context and the object and purpose of the agreement.
A State may sometimes make a reservation when joining a treaty, indicating that it does not accept certain legal effects of particular provisions, provided the reservation is permitted under applicable treaty rules.
States that are parties to treaties must perform their obligations in good faith. A State cannot generally rely on internal law as a justification for failing to comply with an international treaty obligation.
Treaties may end or a State may withdraw according to the terms of the treaty or applicable international rules. Termination does not remove responsibility for obligations that arose while the treaty was in force.
Students should understand treaty formation, consent, interpretation, reservations, good faith performance and the rules governing treaty termination.
Treaty law explains how international agreements create legal obligations. The Vienna Convention provides important rules for understanding how treaties are made, interpreted and applied.