Our urban population is growing dramatically. According to 2001 census, 285 million Indians lived in cities and towns, more than the American population. The residents of large metropolitan areas of Mumbai, Kolkata and Delhi now exceed 10 million each; Chennai, Bangalore, Hyderabad and Ahmedabad exceed 5 million each. And 35 other metropolitan areas have more than a million residents – almost twice as many as in 1991. Projections show that our urban population would grow to about 473 million in 2021, and 820 million by 2051.