The practice was selected ahead of Zaha Hadid and leading Swiss architect Peter Markli to design the £25 million centre for tourism and culture on the shores of Lake Maggiore.
Resembling a 'Baroque city crown', the 10,000m 2building will house a 1,200-seat concert hall as well as permanent and temporary exhibition spaces.
The tourist office and restaurant will sit in a new public garden to the south of the centre, which lies on the edge of the old town.
According to a Caruso St John spokesman, the building will be made from white 'marble-rich' concrete and will 'sparkle in the clear Alpine light.'
The competition judging panel included Peter Zumthor, Roger Diener and John Pawson.