*Why do SAP requires both persistent and runtime reference?* The workflow system stores object references in the container. These object references must be saved in the database whenever there is a context change (switch from one step to the next). This mechanism ensures the workflow can be restarted in case of server down or system crash using transaction SWPC. For this purpose, the workflow system converts the object references in the container from the runtime representation (blue areas) to the persistent representation (green areas) and back again, as required.