The first intergovernmental standard on artificial intelligence, adopted in 2019 and updated since. It is a recommendation rather than a binding instrument, and its influence has been definitional: the OECD's definition of an AI system has been adopted, with modification, in subsequent binding regimes including the EU AI Act.
Tracked here because definitional questions determine scope, and an organisation arguing about whether a particular system is in scope of a statute is frequently arguing about a definition that originated in this document.