After his playing career ended in 2009, Lue became Director of Basketball Development for the Boston Celtics. In 2014, he was hired by the Cavaliers as associate head coach. Lue was promoted to head coach during the 2015–2016 season, replacing the fired David Blatt. That same season, Lue coached the Cavaliers to their first-ever NBA championship and became one of the few rookie coaches in the NBA to ever lead his team to a title. Lue coached the Cavaliers to the NBA Finals in the 2016-2017 and 2017-2018 seasons; in both seasons, the Cavs were defeated by the Golden State Warriors. Lue was terminated by Cleveland in October 2018.