International Environmental Agreements (IEAs) Defined

"an intergovernmental document intended as legally binding with a primary stated purpose of preventing or managing human impacts on natural resources"

To create a systematic and comprehensive catalog of all IEAs requires a clear and explicit definition of each element of the phrase. The definitions used in the IEA Database Project ("agreements", "international", "environmental", and "lineage") are designed:

  • to identify for all database users the basis on which instruments were included or excluded from the database. I do not intend these definitions to imply that agreements not included are less important than IEAs. Rather, I have sought to build a more useful database by carefully defining -- and consistently applying -- explicit definitions with the hopes that others will undertake to do the same in other areas.
  • to foster improvement of the database by allowing those aware of legal instruments that are not included but meet these definitions to email the Project Director;
  • to allow those who prefer alternative definitions to suggest changes to the definition to make the database more useful to all users while retaining clear definitional boundaries.

Defining "international"

What is "international?" Although "international" can have broader meanings, when referring to IEAs, the term usually means intergovernmental. I operationalized this definition to include all agreements to which governments of two or more states have (or are allowed to) become parties but exclude instruments between single governments and non-governmental organizations (NGOs), between single governments and international organizations, and between or among corporations, NGOs, or international organizations.

Defining "agreements"

What is an agreement? As used here, the term corresponds closely to the 1969 Vienna Convention on the Law of Treaties' definition of a treaty as "an international agreement concluded between States in written form and governed by international law" in which states express a "consent to be bound" [Articles 2(1)(a) and 11 through 17] (Aust 2000: 14). For most legal scholars, it is the consent to be bound that is crucial: agreements are the documentation of legally binding arrangements among two or more states, regardless of whether they are designated as treaties, conventions, accords, or modifications of such arrangements (Aust 2000). The difficulty arises, of course, "not with the definition itself, but whether a particular instrument or transaction falls within the definition" (Aust 2000: 14).  I operationalize the definition as: 

  • instruments designated as convention, treaty, agreement, accord, or their non-English equivalents, and protocols and amendments to such instruments; 
  • instruments, regardless of designation, establishing intergovernmental commissions; 
  • instruments, regardless of designation, identified as binding by reliable sources (e.g., by a secretariat, UNEP, or published legal analysis); or 
  • instruments, regardless of designation, whose texts fit accepted terminologies of legally-binding agreements (Aust 2000: 404).  

I intentionally exclude intergovernmental "soft law," such as action plans, agreed measures, codes of conduct, declarations, resolutions, and similar policies because they are not binding. I also exclude European Union (EU) directives because they are distinct in several important ways from other international agreements (Burns 2002; Burhenne and Jahnke 1993; Brown Weiss 1997). "Agreements" are distinguished from non-binding instruments based on words found in the title of the agreement, as delineated in the following tables:  

Agreements - terms from title of instrument used for initial determination as binding instrument

Category Search terms used
Agreement Accord, Act-Agreement, Act-Commission, Act-Treaty, Acuerdo, Adjustment, Agreement, Arrangement-Agreement, Articles of Association, Charter-Agreement, Constitution, Convencion, Convenio, Convention, Convenzione, Covenant, Exchange of Letters Constituting An Agreement, Exchange of Notes Constituting An Agreement, Grant Agreement, Instrument, Interim Agreement, Interim Arrangement, Interim Convention, Loan Agreement, Provisional Understanding, Statute, Statute-Commission, Supplementary Treaty, Tratado, Treaty
Amendment Agreement-Amendment; Amendment; Arrangement-Amendment; Extension
Other Modification Denunciation; Exchange of Letters Modifying an Agreement; Exchange of Notes Modifying an Agreement; Proces-Verbal
Protocol Optional Protocol, Protocol, Protocole, Protocolo, Supplemental Agreement, Supplementary Agreement, Supplementary Arrangement, Supplementary Protocol

Non-agreements - terms from title of instrument used for initial determination as non-binding instrument

Category Search terms used
Amendment-Technical Annex Amendment-Technical Annex
Annex Annex; Appendix
Arrangement Arrangement; Institutional Arrangement
Center Center
Commission Commission; Committee; Organization; Working Group; Working Party
Declaration Charter; Communiqu? Conclusions; Consensus; Declaraci?; Declaration; Decree; Final Act; Mandate; Negotiations; Proclamation; Statement
Directive Directive
Exchange of Notes Exchange of Letters; Exchange of Notes
Memorandum of Understanding Acuerdo-Memorandum of Understanding; Agreed Record; Agreement-Memorandum of Understanding; Community-COST Concertation Agreement; Memorandum; Memorandum of Agreement; Memorandum of Arrangement; Memorandum of Cooperation; Memorandum of Implementation; Memorandum of Intent; Memorandum of Understanding
National Administrative Order; Law; Lei
Plan of Action Action Plan; Plan of Action; Program; Program of Action; Project; Strategy
Resolution Act; Agreed Measures; Application of Safeguards; Charter-Resolution; Code of Conduct; Decision; Principles of Conduct; Proposal; Provisions; Recommendation; Reglamento; Regulation; Resolution; Rules; Scheme; Study; Undertaking

Defining "environmental"

What is environmental? Environmental is the most difficult of the three elements of the phrase to define in a commonly accepted way. Most of the divergence noted among other efforts to catalogue IEAs stems from environmental being "a term that everyone understands and no one is able to define" (Caldwell 1980: 170, cited in Birnie and Boyle 2002: 4). Indeed, two authors who analyzed the United Nation's Environment Programme's catalog of IEAs rejected eight as having "no significant environmental content" (Haas and Sundgren 1993: 404). The definition used here seeks to categorize agreements in ways that correspond to most scholars' and practitioners' distinctions between environmental and nonenvironmental. The definition intentionally errs in being too broad (assuming those with narrower definitions can more readily discard included agreements then identify excluded ones) while trying to avoid including agreements most scholars and practitioners would not classify as environmental.

The Project defines agreements as environmental if they seek, as a primary purpose, to manage or prevent human impacts on natural resources; plant and animal species (including in agriculture, since agriculture modifies both); the atmosphere; oceans; rivers; lakes; terrestrial habitats; and other elements of the natural world that provide ecosystem services (Daily 1997). As agreement's "primary purpose" was operationalized by searching for terms corresponding to this conception in agreement titles, preambles, or articles specifically designating agreement goals [search terms delineated in various tables below]. This excludes agreements addressing human health; conflict; cultural preservation; trade; uses of oceans, lakes, and rivers; outer space, nuclear radiation, transportation, weather, labor, and similar issues unless those agreements addressed environmental issues as a primary concern. The definition also excludes agreements whose effects are environmental, if that was not a primary purpose. A broader definition that includes agreements based on their having environmental effects, like that adopted by Burhenne (1974-2002), captures agreements on trade, regional economic integration, worker protection, and arms control. There may be considerable value in this expansive definition, but it (a) diverges significantly from common usage and (b) has the analytic drawback of requiring that agreement effects be identified before they can be categorized as environmental and, if used literally and consistently, of precluding analysis of why some environmental agreements fail (because those that have no environmental effects would be defined as not environmental). The more restrictive, purpose-based definition used here skirts these problems and also allows analysis of how, if at all, agreements intended to address environmental degradation differ from those intended to address other topics of international concern. 

Nature - general environmental protection

This category seek to capture agreements related to efforts to conserve, manage, preserve, and protect natural resources, natural systems, and wilderness or to foster sustainable development. Coding terms used for INCLUSION are:

Nature charter for nature; conservation; conservation of nature; ecosystem; environment; global change research; green corridor; natural forest ecosystem; natural heritage; natural park; natural resources; natural state; nature conservation; nature protection; protection of nature; rational exploitation; rational management; rational nature use; Remote Sensing For Earth Resources; sustainable and integrated management; sustainable basis; sustainable development; sustainable housing; sustainable management; sustainable tourism; sustainable use; sustainable utilization; wilderness


This category and subcategories seeks to capture all agreements aimed at protecting or managing human interactions with plant and animal species. It includes all agreements related to fish and fisheries management as well as all agreements related to agriculture (although not including commodity agreements). Coding terms used for INCLUSION are:

Species biodiversity; biological diversity; endangered species; microorganisms; wildlife
Species/Agriculture agribusiness; agricult; agro-indus; sanidad agropecuaria
Species/Agriculture/Fauna agricultural plants; animal health; cattle; diseases in livestock; epizootic; farming; foot and mouth disease; grazing; livestock; meat; trade in live animals; veterinary; zoosanitaire; zoosanitary
Species/Agriculture/Fauna/Fish aquacult
Species/Agriculture/Fauna/Flora sanitary and veterinary; veterinary and sanitary; veterinary-sanitary
Species/Agriculture/Flora codex alimentarius; fertilizer; locust; phylloxera; phytosanitaire; phytosanitary; protect harvests; quarantine; vegetable
Species/Fauna animal; fauna; game; hunt; wild animals
Species/Fauna/Bird aquatic warbler; bird; bustard; curlew; siberian crane; waterfowl
Species/Fauna/Fish fish; freshwater fish
Species/Fauna/Fish/Ocean anadromous; atlantic cod; capelin; catadramous fish; driftnet; herring; living aquatic resources; living water resources; lobster; marine fisheries; marine living resources; marine resources; maritime resources; plaice; pollock; salmon; shark; shrimp; sponges; squid; tuna; turtle
Species/Fauna/Mammals bats; bukhara deer; elephant; goat; ivory marketing; mammal; polar bear; reindeer; rhino; tiger; trapping; vicuna
Species/Fauna/Mammals/Marine/Fish cetacean; dolphin; seal; whal
Species/Flora crop diversity; field of plants; flora; forest; greenery; lumber; plant diseases; plant genetic resources; plant protection; planting material; poplar; protection of new varieties of plants; protection of plants; shipments of plants; timber; tree


This category and subcategories seeks to capture all agreements related to all forms of pollution, whether affecting air, land, oceans, or freshwater systems at regional or global scales. Coding terms used for INCLUSION are:

Pollution activities dangerous to the environment; ballast water; corrosive and poisonous substances; corrosive substances; hazardous chemicals; industrial accidents; inflammable substances; natural and technological disasters; noxious; pesticides; poisonous; pollut
Pollution/Air air pollution; air quality; climate change; el nino; fumes discharged from the smelter; fumes emitted from the smelter; global warming; greenhouse gases; monitoring of the stratosphere; ozone; protection of the atmosphere; radioactivity of the upper atmosphere
Pollution/Land white lead in painting
Pollution/Ocean dumping from ships and aircraft; dumping of wastes and other matter; harmful anti-fouling systems; pollution from ships; protection of the waters
Pollution/Ocean/Oil hydrocarbon spills; oil pollution; oil spills; pollution by hydrocarbons; pollution by oil; protection of the black sea; sea by oil
Pollution/Ocean/Oil/Wastes oil and other harmful substances; oil or other harmful substances
Pollution/Wastes hazardous and other waste; hazardous and radioactive waste; hazardous waste; waste

Habitat and oceans

These categories seek to capture agreements related to particular ecosystems, including the ocean. With respect to ocean protection, agreements related to ocean exploration and ocean science are also included. Coding terms used for INCLUSION are:

Habitat  arctic; alp; amazon; antarctic; natural habitat; protected area
Habitat/Land  soil; desertification; drought; dry and barren land; landscape; wetland
Habitat/Marine coral reef
Ocean coastal environment; coastal management; coastal zone management; deep seabed; exploration of the northern seas; exploration of the sea; hydrographic; marine environment; marine science; oceanographic; protection of the wadden sea; scientific exploration

Freshwater resources

This category and subcategories seeks to capture agreements related to regulation of lakes and rivers. In most cases, agreements to protect freshwater resources are designated by the name of the relevant water body with little specificity in the title as to what environmental aspect is being protected. I have assumed the word "protection" of a river or lake involves environmental protection. In other cases, however, I have used the preamble in an attempt to distinguish environmental protection of freshwater resources from those agreements respecting rivers or lakes that only target navigation. Coding terms used for INCLUSION are:

FreshwaterResources aral sea; boundary waters; colorado river water; common works; congo river; conserving water supplies; construction of a temporary cofferdam at niagara; Conveying Capacity Of The International Boundary Segment Of The Colorado River; Cooperation In The Field Of Water Resources; danube river; dephosphatation of the waters; development of the mirim lagoon; development of the resources of the River Gambia; development of the rhine; development of the water resources; distribution of water; diversion of the niagara river; diversion of water; flood control; flood warning; full utilization of the nile waters; gambia river; ganges; hydrological resources; improvement of the resources of the upper basin ; Improvement Of The Waters Of Lake Titicaca; indus waters; irrigat; lake; level of rainy lake; limpopo basin; Management Of Border Waters; management of the inn river; Management Of The River Koliba; management of water resources; mekong; mosel river; parana; pilcomayo; plata; prevent floods; Protect Water And Nature; protection and rational use of transborder water resource; protection and use of transboundary watercourses and international lakes; protection of the elbe; protection of transborder rivers; protection of transborder water resources; protection of transboundary rivers; rectification of the course of the rhine; regulate the level of lake of the woods; regulation of lake inari; regulation of lake lugano; regulation of the rhine; regulation of water; rehabilitation and management of the danube; remedial works at niagara falls; rio duero; rio grande; rios mino; river; river gambia; sava river; senegal river; shared water resources; shared watercourse systems ; shared watercourses; Sharing Of The Ganges Waters; sleswig; Tisza/Tisa ; titicaca; use and hydraulic improvement; Use Of The Nestos River Waters; use of the river nile; use of the waters; use of water and energy resources; use of water resources; utilization of boundary water; utilization of its water; utilization of the rapids of the uruguay river ; utilization of the resources of the Chad Basin; utilization of the river; utilization of the water; utilization of the yarmuk waters; utilization of the zambezi; utilization of transboundary water; utilization of water; water control; water economy; water management; water protection; water quality; water resource management; water resources exploitation; water resources management; weir
FreshwaterResources/Energy diversion for power purposes of additional waters of the niagara river; diversion for power purposes of waters of the niagara river; diversions of water for power production purposes; hydraulic power
FreshwaterResources/Pollution colorado river salinity; detergents; eutrophication; improvement to the conveying capacity of the international boundary segment of the colorado river; management of the rhine; protection of the oder; protection of the rhine; watercourse

Energy, nuclear issues, and conflict

This category and subcategories seeks to capture agreements that address energy production, including nuclear energy. Those related to nuclear weapon free zones; nuclear weapon testing; nuclear accidents; and radioactive waste are also included, although the numerous IAEA nuclear safeguard agreements. Agreements related to conflict are EXCLUDED as non-environmental with the exception of those related to bacteriological, chemical, and toxin weapons. Coding terms used for INCLUSION are identified here:

Energy electric; energy; gas turbine power plant; power plant; power station; water power
Energy/Alternative clean energies; geothermal; Hydro-Energy Resources; photovoltaic; solar heating; Use Of Fuel-Energy And Water Resources
Energy/Freshwater hydroelectric
Energy/Nuclear accidents with possible radiological consequences; atomic reactor; carriage of nuclear material; heavy water power reactor; nuclear energy; nuclear installations; nuclear power; nuclear research; nuclear transfers; processing of uranium; radiation protecton; reprocessing of special nuclear material; Transportation Of Highly-Enriched Uranium ; tritium
Energy/Nuclear/Accident chernobyl; liability in the field of nuclear energy; liability of operators of nuclear ships; nuclear accident; nuclear damage; nuclear emergency; nuclear incident; nuclear safety; radiation accident; radiation safety; radioactive contamination; radiological disaster relief; radiological protection; reactor safety; safety of nuclear power plants
Energy/Nuclear/Pollution physical protection of nuclear material
Energy/Nuclear/Pollution/Wastes radioactive waste
Weapons/Environment bacteriological methods of warfare; chemical weapon; toxin weapon
Weapons/Environment/Nuclear nuclear free zone; nuclear test; nuclear weapon free zone; nuclear weapon test; prohibition of nuclear weapons; underground nuclear explosion

Defining "lineage" and "sequence" and distinguishing them from Subject lists

A lineage is any set of legally-related agreements that are linked by the fact that they modify, replace, extend or otherwise constitute agreements that have a legal relationship to each other. The lineage concept -- and allowing browsing of lineages based on knowing one agreement in a lineage -- is intended to help scholars and practitioners see the legal development of an issue area in ways that are not usually readily apparent. 

For example, the marine pollution (MARPOL) lineage includes the original 1954 OILPOL agreement; the 1962, 1969, and 1971 amendments to that agreement; the 1973 MARPOL agreement that replaced the 1954 agreement; the 1978 Protocol to the MARPOL agreement; and numerous amendments of the 1973/78 MARPOL agreement as well as several separate related conventions. 

The Sequence Number for a lineage is a numbering system devised to show the legal sequence of agreements, using the following conventions:

  • Hundreds are used to designate agreements (e.g., 100.00 is the first agreement in a lineage, 200.00 is the second agreement in a lineage, 300.00 is the third agreement in a lineage).
  • Units are used to designate protocols (e.g., 601.00 is the first protocol to the sixth agreement in a lineage, 307.00 is the seventh protocol to the third agreement in a lineage). 
  • Decimals are used to designate amendments (e.g., 103.01 is the first amendment to the third protocol of the first agreement in a lineage, 205.04 is the fourth amendment to the fifth protocol of the second agreement in a lineage).

Subject lists are simply lists of agreements that contain the same words or phrases in them. Thus, there are a variety of IEAs that protect birds in various ways, but they are parts of quite distinct legal lineages, having been signed by different countries in different regions and with no legal connections between them.


Aust A. 2000. Modern treaty law and practice. Cambridge: Cambridge University Press

Birnie PW, Boyle AE. 2002. International law and the environment. Oxford: Oxford University Press

Brown Weiss E, ed. 1997. International compliance with nonbinding accords. Washington, DC: American Society of International Law

Burhenne WE, ed. 1974-2002. International environmental law: multilateral treaties. Bonn: Kluwer Law International

Burhenne WE, Jahnke M. 1993. International environmental soft law: collection of relevant instruments. Dordrecht: M. Nijhoff

Burns W. 2002. American Society of International Law Wildlife Interest Group Listing of Treaties and Soft Law Agreements

Caldwell LK. 1980. International environmental policy and law. Durham, NC: Duke University Press

Daily GC, ed. 1997. Nature's services : societal dependence on natural ecosystems. Washington, DC: Island Press

Haas PM, Sundgren J. 1993. Evolving international environmental law: changing practices of national sovereignty. In Global accord: environmental challenges and international responses, ed. N Choucri, 401-29. Cambridge: MIT Press