With an information technology sector growing at the rate of 70% a year, the Indian city infamously associated with the "black hole" is undergoing a radical transformation.
High-rish buildings are sprouting up as part of a future IT hub
So how has Kolkata, with its proudly Communist government, become the city of choice for many multinational companies?
And is this enormous growth sustainable? Tanya Datta met some of the city's winners and losers.
BBC Radio 4's Crossing Continents was broadcast on Thursday, 23 March, 2006, at 1102 GMT.
The programme was repeated on Monday, 27 March, 2006, at 2030 BST.
Presenter: Tanya Datta
Producer: Linda Pressly
Web Producer: Nathalie Knowles
Editor: Maria Balinska