Manage Department Item Mappings
Path: Administration > Manage Items > Item Mapping > Department Item Mapping
First, select a department, then select the items that should be mapped to that department. Then select "Add Items to Department", then all the selected items will be mapped to the selected department.
To see the items that have already been mapped, select "Fill Items Added for Department".
To remove items added to a department, select the relevant items and then select "Remove Selected".