You can easily make an employee a leaver when using Polaris Data; the following article helps explain how to do so.
Firstly, you will need to open the employee's record within staff maintenance.
Next, navigate your way along the tabs to the "Leavers" section (the aeroplane).
Once in the leavers tab, you will need to tick the box next to "This employee is a leaver".
After this box has been ticked, it will bring up the opportunity for you to enter a leave date, exit interview date, reason for leaving etc. Please note that the leaving date and reason for leaving sections are mandatory fields.
Once this has been completed, the employee will be made a leaver within the system.
A leaver can be reinstated in the future; there is a link below to an article explaining how to do this.