How do I apply a Group Policy Object at the Organizational Unit (OU) level?
There are a couple of different ways to do this. My preferred method is to open Active Directory Users and Computers, navigate to the organizational unit (OU) in question, right click and select properties. Select the Group Policy tab and add the Group Policy element you would like to apply. Keep in mind that some OU's (notoriously the "Computers" and "Users" OUs) do not allow you to apply Group Policy Objects at the OU level. This is perhaps the biggest reason for creating additional OUs for all your computer and user accounts to reside in.