From the Settings menu click Agents
This brings up the Agent List, containing both inside and outside Agents
Click New Outside Agent
Input the Company Name (Required)
If desired, input the Agent's email address, First and Last Name, and/or physical address.
Click Save in the bottom right hand corner.
This Agent can now be added to Vouchers as needed.
*You can also add outside agents during the voucher creation process by following these instructions.