Louis Tyrone Williams (born October 27, 1986) is an American professional basketball player for the Atlanta Hawks of the National Basketball Association (NBA). He was drafted directly out of high school by the Philadelphia 76ers with the 45th overall pick in the 2005 NBA draft. He is a 3-time NBA Sixth Man of the Year. As of March 2019, he is the NBA's career leader in points off the bench.

Williams spent seven seasons with Philadelphia before signing with the Atlanta Hawks in 2012, playing two seasons there before being traded to the Toronto Raptors in the 2014 offseason. He spent a season with the Raptors and then signed with the Los Angeles Lakers from 2015 until the middle of the 2016–17 NBA season, when he was traded to the Houston Rockets. After finishing the season with the Rockets, he was then traded in the 2017 offseason to the Los Angeles Clippers.