A Telephone Control Officer (TCO) monitors the telephone activity for a certain Subscriber group. In this software section, you are creating a TCO Group. Each group contains the Subscribers that are your TCOs.
There are two Subscribers types when accessing a TCO group. First, there are the Selected Subscribers (Subscribers who are TCOs). You will need to add the person as a subscriber and then select them to be a TCO. The second type of subscriber is the Managed Subscriber managed by the TCO. Again, you will need to add each subscriber and select the appropriate person in the TCO field.