In the Facilites tab of Emplyee Preferences you can effect users abilities to edit calendar items.

Parts of the Facility Tab
| Unassigned Activity Patron |
Enter a default unassigned activity patron here as a placeholder for personnel assigned to specific project tasks to be used while those personnel are still being set up. It is also used in the volunteer/personnel tab in events and dates to bulk set up the people needed to work a performance. |
| Others who can edit my tasks |
Here you can assign delegates who can edit your calendar task information. This prevents others from changing your tasks by supplying a list. Use the green plus and red minus buttons at the bottom left of the table to add or remove patrons from this list.
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