Introduction

This manual is a useful aid for finding treaties (pacts, conventions, agreements, convenants, charters, protocols). It consists of a short explanation on terms and definitions used, followed by an overview of sources of texts and ratification information of treaties.

Law of Treaties: Vienna Convention on the Law of Treaties 

Law of treaties constitutes all law concerning the coming about and the effect of treaties, which is stipulated in the Vienna Convention on the Law of Treaties (1969).

Ratification/accession

Treaties only apply to states when states have officially committed themselves by filing an instrument of ratification or accession with the depositary.

Bilateral treaties enter into force when both parties have filed an instrument of ratification with the depositary. Multilateral treaties enter into force after ratification by a number of states or after a lapse of a certain period of time as stipulated by the treaty.

Reservation

A treaty is the result of negotiations. The content and meaning of provisions may vary for parties concerned. A reservation can be made when the text of the treaty is accepted ("adopted") by a state. This means that it is explicitly stated that the committing state does not wish to be committed to certain provisions of the treaty in question. 

Protocol

Protocols consist of supplements and changes to treaties which have already come into force. Protocols are separate treaties, often only those states can become a party to these protocols which were already a party to the previous treaty.
An 'optional protocol' can be concluded when states are prepared to enter into more far-reaching obligations than other states. These more far-reaching obligations are then included in an optional protocol, which has to be accepted separately. 

Depositary

The depositary monitors the administration of a treaty (entry into force, ceasing of force, ratification etc). The depositary sends notifications to all parties concerned when a treaty is amended. The Kingdom of the Netherlands is depositary for around hundred treaties. It is stipulated in the text of a treaty which state or international organization is appointed depositary.

Sources for finding treaties

Sources of (treaty) texts, complementary indexes and ratification information are arranged chronologically.  First, an overview of the sources for the most recent treaties, followed by the sources of older treaties and concluded by an overview of sources arranged by field of law.

International Legal Materials (ILM)
Texts of well-known and other treaties, draft versions and recent treaties, which have not yet been published in the United Nations Treaty Series.

United Nations Treaty Collection (UNTS)
Texts of bilateral and multilateral treaties since 1946, in their original language, sometimes complemented by translations in English or French.

United Nations Treaty Collection Cumulative Index Online
Chronological and alphabetical index on the UNTS.

Status of Multilateral Treaties deposited with the Secretary-General
Ratification information of the most important treaties concluded within the United Nations.

World Legal Information Institute
Access to bilateral and multilateral treaties (full text), ratification information and links to other indexes and collections concerning treaties.

Bulletin of Treaties (Tractatenblad)
Access to all treaties (full-text) applicable to The Netherlands as from 1951. Treaties dating from before 1951 are published in the Staatsblad.

Treaties - Government of the Netherlands
Access to the Treaty database, news articles and several other sources of information, such as the monthly notifications of the Bulletin of Treaties and depositary notifications.
There is also an overview of treaties in preparation.

American Journal of International Law (AJIL) - Supplement
Access to older treaties (full text). Use the index of Bowman & Harris to find a treaty.

Oxford Historical Treaties
Access to the full-text Consolidated Treaty Series (Clive Parry). Contains treaties of all nations from 1648 through 1919. Searchable by title, treaty party, citation, date or date range.

Human Rights Library of the University of Minnesota
Access to treaties (full text) and links to search engines concerning human rights.

OHCHR jurisprudence
Includes documents from the database of the Netherlands Institute of Human Rights (SIM).

United Nations Human Rights Treaties
Access to human rights treaties, changes and ratification data.

Human Rights Treaty Bodies - General Comments
Texts, ratification data and commentaries on the various United Nations human rights treaties.

International Labour Organization
Texts and documents of treaties and directives including ratification data per state.

Normlex - Information System on International Labour Standards
Ratification data of ILO treaties. with the ability to search on keywords - C(onvention, P(rotocol) or R(ecommendation) number.

Ecolex
Important source for finding environmental treaties. Contains signing and ratification data.

EUR-Lex
Access to the complete texts of the treaties of the European Union and the European Communities. Contains founding treaties, accession treaties and other treaties and protocols.

Council of Europe Treaty Office
Treaties, protocols, ratification data, etc of the Council of Europe, arranged chronologically from 1949 until now. 

Additional sources for treaties

Flare Index to Treaties
Index to more than 2000 treaties dating from 1353, bilateral as well as multilateral, with references to call numbers for paper and (if available) online sources. 

World Treaty Index
References to almost every treaty from the 20th century.

Multilateral Treaties: index and current status / M.J. Bowman & D.J. Harris (1984) - References to treaties as from 1856.

Commentaries

Provide information on how to interpret terms in legislative acts and explain the legislative history and policy background of acts.

Find a specific commentary (resources)

1) CataloguePlus: Click Advanced search to the right of the search box.
2) Enter in the first search field a combination of commentar* + a specific subject/field of law and select Material Type: Books.
3) Click Search and refine the search results by selecting Library: Juridische Bibliotheek to the right of the results.

Travaux preparatoires

Preparatory works: documents, such as memoranda, minutes of conferences, and drafts of a treaty under negotiation for the purpose of interpreting the treaty.

Find specific travaux preparatoires

1) CataloguePlus: Click Advanced search to the right of the search box.
2) Enter in the first search field a combination of travaux preparatoires + a specific treaty and select Material Type: Books.
3) Click Search and refine the search results by selecting Library: Juridische Bibliotheek to the right of the results.

Find travaux preparatoires of UN treaties

Historic Archives / Audiovisual Library of International Law
Select a field of law and click on a specific treaty. The ‘Documents’ tab at the top of the page provides references to the preparatory documents.

Other research guides

There are many online research guides available concerning finding treaties; here is a small collection:

• Globalex - An Introduction to Sources for Treaty Research
• Peace Palace Library - Research Guide Treaties
• Public International Law (pdf) - Electronic research guide of the American Society of International Law (ASIL)

Literature

• Handbook on good treaty practice / J. Barret, R.C. Beckman (2020)
• The law of treaties / Lord McNair (1986)
• The law of treaties: an introduction / R. Kolb (2016)
• Max Planck Encyclopedia of Public International Law - Treaties / M. Fitzmaurice
• The Oxford guide to treaties / D. B. Hollis (2nd ed. 2020)
• The Oxford handbook of United Nations treaties / S. Chesterman, D. M. Malone, S. Villalpando (2019)
• Research handbook on the theory and practice of international law making / C. Brölmann, Y. Radi (2016)
• The Vienna Convention on the Law of Treaties / I.M. Sinclair (1973) and idem (2nd ed 1984)

Other books containing treaties and information on treaties can be found in the library at section (call number) AA.