ISO 20121 is a management system standard designed to help events industry organizations improve the sustainability of their events-related activities, products and services. ISO 20121 is a management system standard designed to help events industry organizations improve the sustainability of their events-related activities, products and services. ISO 20121 covers all types and sizes of organizations involved in the events industry – from caterers, lighting and sound engineers, security companies, stage and venue builders to independent event organizers and event teams in the corporate and public sector.