Communications can be added anywhere in the system by pressing the Communications button. There are many Communication buttons in the system and what the Communication is linked to will depend which Communication button is pressed, for example.
All the Communications can be viewed in the Communication tabs, however the above options allow you automatically add more details linked to the Communication.
Wherever the button was pressed, the Links page of the Communication window also allows you to link the Communication with other areas of the system.
More details about the Communication Window can be viewed in Communications Overview.
Adding a Communication