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If COUs are defined, they can be flat (no hierarchy, all are at the same level), or a COU can have a parent COU (in which case a hierarchy is implied).

Prior to Registry v3.3.0, if COUs are defined all CO Person Roles are required to be associated with a COU. (Existing CO Person Roles are not assigned COUs if COUs are enabled after they are created; CO-322.) As of Registry v3.3.0, this behavior is configurable via Configuration > CO Settings > Enable Empty COUs. If enabled, it is possible to create a CO Person Role that is not associated with any COU. COU Administrators will be unable to edit the attributes associated with that CO Person Role.

CO Departments

CO Departments are primary objects within Registry, which means that they are intended to store representations of external objects (just like CO People). CO Departments can attach to either a CO or a COU, and can be used to store a number of attributes about the department, including telephone numbers, email addresses, URLs, identifiers, and the sets of people associated with specific responsibilities within the department. CO Departments can be used to support various use cases:

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