A graduate in political sciences at the University of Turin, where he worked as a researcher until 1975, Chiamparino started his political career that same year as head of the Italian Communist Party in the Town Council of Moncalieri, his native city. After the birth of the Democratic Party of the Left, he joined that party and was elected as deputy in 1996, after having surprisingly been defeated in 1994 in the left-leaning district of Mirafiori against the centre-right candidate Alessandro Meluzzi.
He was elected mayor of Turin in 2001, succeeding to Valentino Castellani and then re-elected in May 2006 with 66,6% of votes, defeating centre-right candidate Rocco Buttiglione.
