International Organization for Standardization
ISO is a non-governmental organization established in 1947 to promote the development of standardization and related activities in the world. It comprises a network of national standards institutes for 140 countries working in partnership with international organizations, governments, industry, business and consumer representatives.
Further details may be found at the ISO website.
It is important to note that ISO is not an acronym but a derivation of the Greek isos, meaning equal.