This document specifies requirements for an event sustainability management system for any type of event or event-related activity, and provides guidance on conforming to those requirements. This document is applicable to any organization that wishes to: a) establish, implement, maintain and improve an event sustainability management system; b) ensure that it is in conformity with its stated sustainable development policy; c) achieve the intended result(s) of its event sustainability management system; d) demonstrate voluntary conformity with this document by first party (self-determination and self-declaration); second party (confirmation of conformance by parties having an interest in the organization, such as clients, or by other persons on their behalf); an independent third party (e.g. a certification body). This document has been designed to address the management of improved sustainability throughout the entire event management cycle. Additional guidance and information is provided in annexes to support its implementation.