Bill O'Brien, American football player and coach
William James O'Brien (born October 23, 1969) is an American football coach who is currently the offensive coordinator and quarterbacks coach at the University of Alabama. O'Brien previously served as the head coach of the Houston Texans of the National Football League (NFL) from 2014 to 2020 and at Pennsylvania State University from 2012 to 2013. He also served as the general manager of the Texans in 2020.

O'Brien began his coaching career in 1993 at Brown University before spending more than a decade coaching in the Atlantic Coast Conference (ACC). He joined the New England Patriots in 2007, where he eventually served as quarterbacks coach and offensive coordinator in 2011. In 2012, he was hired by Penn State to take over a program that had just endured the Penn State child sex abuse scandal. In his first season as head coach, he led the team to an 8–4 record and won ESPN's National Coach of the Year award. After the 2012 season, O'Brien garnered significant interest to return to the National Football League (NFL) as a head coach and interviewed with both the Philadelphia Eagles and the Cleveland Browns. O'Brien decided to stay at Penn State, citing that it would send a poor message to leave after just one season. After his second season, he left Penn State to become the head coach of the Texans.