Isiah Lord Thomas III (born April 30, 1961 in Chicago, Illinois) is an American former professional basketball player and coach, and is currently the president of basketball operations for the NBA's New York Knicks. His name is spelled "Isiah" but pronounced the same as the more common "Isaiah".

Thomas played for Indiana University and was named to the 1980 U.S. Olympic team, although the U.S. boycotted that year's games. He left IU in 1981, after a sophomore year in which he led the Hoosiers to the NCAA national title; he earned a bachelor's degree from IU several years later.

From 1981 to 1994 Thomas had a stellar career as a point guard with the Detroit Pistons; among his many achievements, he was a 12-time NBA All-Star, and is the Pistons' all-time leading scorer. He led the Pistons to NBA titles in 1989 and 1990. A few years after his retirement, Thomas became the owner of the Continental Basketball Association from 1998 to 2000. From 2000 to 2003 he coached the Indiana Pacers. In 2001, Isiah Thomas was elected to the Basketball Hall of Fame.

One of Thomas's best known performances came in an NBA Finals game against the Los Angeles Lakers. Although he badly twisted his ankle in the game, Thomas continued to play. While hobbling and in obvious pain, Isiah was still able to score 26 points in a single quarter of that contest, a NBA Finals record.