On stage, Smith won three Drama-Logue Awards for his performances in Billy Budd, Idiot's Delight, and Green Grow the Lilacs.

After That '70s Show ended, Smith played Senator Blaine Mayer in the seventh season of the action thriller 24, and portrayed Dick Clayton in the CBS series Worst Week.

He enjoyed a recurring role as a rogue FBI agent in Seasons 3–5 of the NBC (later CBS) series Medium, appearing in later episodes as a ghost after his character's death.

He also has an extensive voice acting résumé, appearing in computer games such as Fallout Tactics: Brotherhood of Steel, and FreeSpace 2, and on a number of animated series.

He played the voice of Bob Johnson on Squirrel Boy and Kanjar Ro in Green Lantern: First Flight and starred as the sheriff in Last of the Dogmen.