Hi
if I understand you correctly, you want to make a group of users administrators for some client machines. If this is correct, it has nothing to do with "delegation of control" in Active Directory, as you do not want to delegate some administrative rights over Active Directory objects
When you want to make some users or a certain group administrators of client machines, you should evaluate using the "Restricted groups" setting in Group Policy. By using "Restricted groups", you can configure who should be a member of a certain group - by this, you could make a certain Domain group to always be a member of the local "Administrators" group of the client workstations. Make sure that you include ALL groups that should belong to the local Administrators group in the "Restricted Groups" policy as this is a "replace" rather than a "merge" policy
For such a topic, I recommend that you use a computer startup script in Group Policy to check if the Domain group is a member of the local Administrators group. If not, the script can add the group.
