You use this table to set up additional approvers. Many companies will set up a hierarchy of users who are required to approve specific documents before they are sent to customers or vendors. But in some cases, you may need a different approval structure that includes an additional approver outside the normal hierarchy of approvers. For example, a controller in the finance department or a general manager in a small company might need to approve certain documents.
Additional approvers can only be used if you have selected Blank in the Approval Type field in the Approval Templates window.