Region lockouts can be used when a group needs to have a final say on changes to trails, points of interest, or polygons in a region. The lockout controls can be found in a region's admin page, under the permissions tab.
When editing a group's permissions, the panel for 'Lockout Activities' should be visible.
In order to lock out external groups and users (not the current group that you are editing), toggle 'on' the activities that the group should fully own.
Now looking at the permissions overview, the activity icons that have been locked out will now show up under the 'lockout' column.
If another user (that has the ability to make changes without approval) submits or edits a point of interest, a Polygon, or trail that is linked to the locked out activity type, that user will need approval from the group that has the lockout placed on them.