Unable to save a form with missing required fields

I have a form, with required fields, as part of the new hire process. I would like to make sure the user fills in the required fields before closing/saving the form.

I have a custom script that highlights the missing required fields when the complete/validate button is clicked.

This, however, doesn't stop the user from saving the form. As a result, we are getting incomplete forms returned.

Is there a way to stop the user from saving the form until the required fields are filled ?

Thanks in advance.

Aditya