The International Hydrographic Organization (IHO) is an
intergovernmental organisation An intergovernmental organization (IGO) is an organization composed primarily of sovereign states (referred to as ''member states''), or of other organizations through formal treaties for handling/serving common interests and governed by interna ...
hydrography 300px, Table of geography, hydrography, and navigation, from a 1728 '' Cyclopaedia''. Hydrography is the branch of applied sciences which deals with the measurement and description of the physical features of ocean The ocean (also the sea ...
. As of December 2021 the IHO comprised 96 Member States. A principal aim of the IHO is to ensure that the world's seas, oceans and navigable waters are properly surveyed and charted. It does this through the setting of
international standard An international standard is a technical standard A technical standard is an established norm Norm, the Norm or NORM may refer to: In academic disciplines * Norm (geology), an estimate of the idealised mineral content of a rock * Norm (philoso ...
s, the co-ordination of the endeavours of the world's national hydrographic offices, and through its capacity building program. The IHO enjoys observer status at the
United Nations The United Nations (UN) is an intergovernmental organization aiming to maintain international peace and international security, security, develop friendly relations among nations, achieve international cooperation, and be a centre for harm ...

United Nations
, where it is the recognised competent authority on
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ing and
nautical chart A nautical chart is a graphic representation of a sea area and adjacent coastal regions. Depending on the scale (map), scale of the chart, it may show depths of water and heights of land (topographic map), natural features of the seabed, details ...

nautical chart
ing. When referring to hydrography and nautical charting in Conventions and similar Instruments, it is the IHO standards and specifications that are normally used.


The IHO was established in 1921 as the International Hydrographic Bureau (IHB). The present name was adopted in 1970, as part of a new international Convention on the IHO adopted by the then member nations. The former name International Hydrographic Bureau was retained to describe the IHO secretariat until 8 November 2016, when a significant revision to the Convention on the IHO entered into force. Thereafter the IHB became known as the "IHO Secretariat", comprising an elected Secretary-General and two supporting Directors, together with a small permanent staff (18 in 2020), at the Organization's headquarters in Monaco. During the 19th century, many maritime nations established hydrographic offices to provide means for improving the navigation of naval and merchant vessels by providing nautical publications, nautical charts, and other
navigation Navigation is a field of study that focuses on the process of monitoring and controlling the movement of a craft or vehicle from one place to another.Bowditch, 2003:799. The field of navigation includes four general categories: land navigation, ...

al services. There were substantial differences in hydrographic procedures charts, and publications. In 1889, an International Maritime Conference was held at
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, and it was proposed to establish a "permanent international commission." Similar proposals were made at the sessions of the International Congress of Navigation held at
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Saint Petersburg
in 1908 and the International Maritime Conference held at
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Saint Petersburg
in 1912. In 1919, the national Hydrographers of Great Britain and France cooperated in taking the necessary steps to convene an international conference of Hydrographers. London was selected as the most suitable place for this conference, and on 24 July 1919, the First International Conference opened, attended by the Hydrographers of 24 nations. The object of the conference was "To consider the advisability of all maritime nations adopting similar methods in preparation, construction, and production of their charts and all hydrographic publications; of rendering the results in the most convenient form to enable them to be readily used; of instituting a prompt system of mutual exchange of hydrographic information between all countries; and of providing an opportunity to consultations and discussions to be carried out on hydrographic subjects generally by the hydrographic experts of the world." This is still the major purpose of the IHO. As a result of the 1919 Conference, a permanent organization was formed and statutes for its operations were prepared. The IHB, now the IHO, began its activities in 1921 with 18 nations as members. The
Principality of Monaco Monaco (; ), officially the Principality of Monaco (french: Principauté de Monaco), is a sovereign Sovereign is a title which can be applied to the highest leader in various categories. The word is borrowed from Old French ''souverain'', whic ...

Principality of Monaco
was selected as the seat of the Organization as a result of the offer of
Albert I of Monaco Albert I (Albert Honoré Charles Grimaldi; 13 November 1848 – 26 June 1922) was Prince of Monaco from 10 September 1889 until his death. He devoted much of his life to oceanography, exploration and science. Alongside his expeditions, Albert I ...

Albert I of Monaco
to provide suitable accommodation for the Bureau in the Principality.


The IHO develops hydrographic and nautical charting standards. These standards are subsequently adopted and used by its member countries and others in their surveys, nautical charts, and publications. The almost universal use of the IHO standards means that the products and services provided by the world's national hydrographic and oceanographic offices are consistent and recognizable by all seafarers and for other users. Much has been done in the field of standardization since the IHO was founded. The IHO has encouraged the formation of Regional Hydrographic Commissions (RHCs). Each RHC coordinates the national surveying and charting activities of countries within each region and acts as a forum to address other matters of common hydrographic interest. The 15 RHCs plus the IHO Hydrographic Commission on Antarctica effectively cover the world. The IHO, in partnership with the Intergovernmental Oceanographic Commission, directs the
General Bathymetric Chart of the Oceans The General Bathymetric Chart of the Oceans (GEBCO) is a publicly available bathymetric chart A bathymetric chart is a type of isarithmic map that depicts the submerged topography and physiographic features of ocean and sea bottoms. Their primary pu ...


Establishment of the Chart Specifications Committee and International Charts: # The exploration of the seabed and movements of the sea # Standardization of maritime measurements, hydrographic terminology, marine cartographic products, and geographical information systems for navigation # High efficiency of the rapid dissemination of information on safety at sea # Training of hydrographers and nautical cartographers


Most IHO publications, including the standards, guidelines and associated documents such as the ''International Hydrographic Review'', ''International Hydrographic Bulletin'', the ''Hydrographic Dictionary'' and the ''Year Book'' are available to the general public free of charge from the IHO website. The IHO publishes the international standards related to charting and hydrography, including S-57, ''IHO Transfer Standard for Digital Hydrographic Data'', the encoding standard that is used primarily for
electronic navigational chartImage:enc.jpg, frame, Electronic navigational chart (NOAA) An electronic navigational chart or ENC is an official database created by a list of Members of the International Hydrographic Organization, national hydrographic office for use with an Elec ...
s. In 2010, the IHO introduced a new, contemporary hydrographic geospatial standard for modelling marine data and information, known as S-100. S-100 and any dependent product specifications are underpinned by an on-line registry accessible via the IHO website. S-100 is aligned with the ISO 19100 series of geographic standards, thereby making it fully compatible with contemporary
geospatial data Geographic data and information is defined in the ISO/TC 211 series of standards as data and information having an implicit or explicit association with a location relative to Earth (a geographic location or geographic position). It is also calle ...
standards. Because S-100 is based on ISO 19100, it can be used by other data providers for their maritime-related (non-hydrographic) data and information. Various data and information providers from both the government and private sector are now using S-100 as part of the implementation of the e-Navigation concept that has been endorsed by the UN
International Maritime Organization The International Maritime Organization (IMO, French: ''Organisation Maritime Internationale''; known as the Inter-Governmental Maritime Consultative Organization until 1982) is a specialised agency of the United Nations United Nations Spec ...
. Another in the series of publications of interest is S-23, ''Limits of Oceans and Seas''. The 3rd edition dates back to 1953 while the potential 4th edition, started in 1986, has remained a draft since 2002. It was distributed to IHO members, but its official publication has been suspended pending agreement between
South Korea South Korea, officially the Republic of Korea (ROK), is a country in East Asia, constituting the southern part of the Korea, Korean Peninsula and sharing a Korean Demilitarized Zone, land border with North Korea. Its western border is for ...

South Korea
Japan Japan ( ja, 日本, or , and formally ) is an island country An island country or an island nation is a country A country is a distinct territory, territorial body or political entity. It is often referred to as the land of an in ...

regarding the international standard name of the sea called "
Japan Sea , koreanname = North Korean name , context = north , hangul = , hanja = , rr = Joseon Donghae , mr = Chosŏn Tonghae , lk = East Sea of Korea , koreantext = , koreanname2 = South Ko ...

Japan Sea
" in the 1953 edition.

See also

* World Hydrography Day


External links

* {{Authority control 1921 establishments in Monaco Intergovernmental organizations International organisations based in Monaco International standards Organizations established in 1921 United Nations General Assembly observers Hydrography organizations International geographic data and information organizations