Eritrium System Administrators can manage departments. This task must be done before allowing all the users to tart using Eritrium.
Departments must be managed at the main company window (the company that owns the domain and the one for what you are working).
Look for your company in the options tree at "Customer/Contacts -> Organizations". Select your company and open its management window. Select the tab "Departments":
You can add new departments simply hiting the Green cross located at the right site of the form.