Add collaborators by handle on a project's Team tab.
Roles: Owner, Director, Writer, Editor, Producer, Cinematographer, Sound, Artist, Reviewer.
Assignment is per scene — "give my cinematographer Scene 4" is a real operation, not a convention.
Human team members can hold the same roles the AI crew agents do, with matching permissions.
Live multi-user editing is not built. Two people editing the same scene simultaneously will overwrite each other. Coordinate, or use branches — which share rendered assets and merge cleanly at the asset level.