You can add or remove contacts in a group. Removing a contact from a group doesn’t delete the contact. To delete a contact or a group, see Delete contacts.
Select one or more contacts.
Drag the selected contacts to a group.
Contacts in an Exchange account can belong to only one folder at a time. Any contacts not in a created folder are in the default Exchange Contacts folder.
Select the group, then select one or more contacts you want to remove from the group.
If you don’t see your groups, choose View > Show Groups.
Press the Delete key on your keyboard.
Click Remove from Group.