Lively started his career by appearing in the pilot episode of The Dukes of Hazzard when he was 10 years old. His first film appearance was four years later in the 1983 film Brainstorm. That same year he also had another appearance in The Dukes of Hazzard.
His most recognizable roles came later when he played Rusty Griswold in National Lampoon's European Vacation, and Chris in Night of the Creeps. After that, he appeared in the films Ghost Chase and Maximum Force. In 1993, he appeared in the video game Return to Zork, along with his sisters, Robyn Lively and Lori Lively.
He reprised his role as Rusty Griswold in 2012 in a series of Old Navy holiday commercials featuring the Griswold family.