A familiar face on ITV news since the 1980s, Mr Stewart is an experienced professional who brings gravitas and intelligence to the screen.
His career, however, has been touched by controversy.
The 58-year-old is instantly recognisable as the voice of, quite literally, car crash TV. He hosted Police Camera Action! on ITV,
a job that came to an end when Mr Stewart was forced to resign after his second conviction for drink driving in 2003.
A former war correspondent, he hosted ITV's election night coverage in 2005 as well as of the 2008 US presidential election.
After joining ITN in the 1980s as an industrial correspondent,
he has covered major events including the fall of the Berlin Wall, Royal weddings and the Lockerbie disaster.
Mr Stewart has been co-presenter of ITV's 6:30pm bulletin since September last year.
Other programmes he has presented include Alastair Stewart's Sunday for BBC Radio 5. In 1995, he joined GMTV, where he anchored Alastair Stewart's Sunday Programme until 2001.
A devoted follower of the Rolling Stones, Mr Stewart won the December 2009 edition of Celebrity Mastermind with the band as his specialist subject. When asked by host John Humphrys if there was anybody left he would like to interview, he answered the Pope and Stones lead singer Mick Jagger – clarifying it as Jagger first.