XR systems embed many sensors to capture the real world in 3D. They use them mainly for localization and understanding purposes. But how to structure the captured representation of the real world in a way to provide interoperability among existing XR systems? This webinar will present you the recently published ETSI specifications and available tools to create, modify and store a world representation. The storage takes place as a shared graph on a remote server. With this approach, the world representation specification also supports the creation of large scale XR experiences.