William H. Wisher Jr. is an American screenwriter, known for his work with longtime friend James Cameron on The Terminator and Terminator 2: Judgment Day. In the first Terminator film, William has a brief role as a police officer who has his head smashed into his own police cruiser by the Terminator, who then steals his vehicle and briefly assumes his identity on the police radio band. He also has a cameo appearance in Terminator 2: Judgment Day as a man who takes pictures of Arnold Schwarzenegger's T-800 Terminator getting back on his feet after being thrown through a store window, and as news reporter Bill Tyler in Cameron's 1989 film The Abyss.
Wisher's other screenwriting work includes Judge Dredd, The 13th Warrior and both versions of The Exorcist prequel. He is an uncredited script doctor on two films in the Die Hard series, 1995's Die Hard with a Vengeance and 2007's Live Free or Die Hard (on which he also served as executive producer).