Dropdown list Box

how can i use a conditional list based on a value, that is, we would like the list of approvers to be based on the field Department.
For Eg. If the Dept Actuarial is chosen, the list of Acturial Approvers ONLY will be visible.


You can add a filter in a dropdown list box.

For the following example, I have created a global list with a column which contains the user department.
With the filter, when the user sets the user department in the Department field, the dropdown list User will be filtered by this value.