The International Hydrographic Organization (IHO) (French: Organisation Hydrographique Internationale) is an intergovernmental organization representing hydrography. As of August 2025, the IHO comprised 103 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 standards and through its capacity building programs and offices. The IHO enjoys observer status at the United Nations, where it is the recognized competent authority on hydrographic surveying and nautical charting. When referring to hydrography and nautical charting in conventions and similar instruments, it is the IHO standards and specifications that are normally used. Source: Wikipedia (en)