If a user is apart of an org. group then you would see this on their profile.
Enforce Organization True
If Enforce Organization is true then the person is affected by the organization group that is tagged on their profile.
This means that they will only see people at the same level as them, and below them in the org. structure tree.
We have a org. structure tree:
Len Zill is in Division 1
Me is in Head Quarters 1
Sara Brock is also in Division 1
Amy Way is in Division A
Charles Lee is in Division A
Who can Len Zill see?
Len Zill can see Sarah Brock, Amy Way and Charles Lee. He cannot see Me because he is in an org. group below Me.
Enforce Organization False
If Enforce Organization is false then the person is not affected by the organization group that is tagged on their profile.
They will be able to see everyone in the system.