Federal Bureau of Investigation Assistant Director Skinner made his first appearance in the first season 1994 episode "Tooms". At the start of the series, Skinner was unfriendly towards Fox Mulder because of his belief in the extraterrestrial, while throughout the series run Skinner has moved on to respect and agree with Mulder's idea, which is finally proven in "Requiem", when he saw an Alien spacecraft.
Pileggi received the role of Walter Skinner after "two or three" auditions for the role. Beginning with only a small cameo, his character frequently made more appearances during the second season. Pileggi was honored with numerous awards and award nominations for his portrayal of Skinner.