Managing Work Area Participants
Users with access to a work area are called work area participants. You add users to and remove users from a work area through the Participants tab of the Work Area Properties dialog. This tab is also where you set or change a participant's permissions for folders, documents, or components within the work area.
When no participants are defined for a work area, then work area access rights are inherited from the work area above it. If no participants are defined for a top level work area, then all users in the datasource have access to that work area.