Frank will be Detroit's sixth coach in 11 seasons when the NBA lockout ends and he has a three-year deal with a team option for a fourth year. The person confirmed the move, first reported by Yahoo Sports, to The Associated Press on condition of anonymity Friday because the team hasn't announced the move.
The Pistons fired John Kuester in June after they missed the playoffs in both of his two seasons.
Frank was a Boston Celtics' assistant coach last season. He also was the head coach in New Jersey for five full seasons.