From 1980 to 1983, Schillerstrom prosecuted cases as an Assistant State's Attorney for DuPage County. He later served as chairman of the DuPage County Board from December 1998 through December 2010.
Schillerstrom worked as an Assistant State's Attorney in DuPage County from 1980 to 1983. Afterward, he was the chairman of the DuPage County Board from December 1998 until December 2010.