Substitutes are important to the success of the total school program and are expected to perform in place of the regularly scheduled employee as directed by the school administrator. In the regular employees' absence, substitutes carry out all duties assigned to facilitate the instructional process and to provide for a safe, educationally productive environment in the classroom, the school or the workplace.

The Sub4Loudoun website includes information about how to become a sub, important information for current subs, and quick links to various LCPS departments and other resources.