India’s urban population is second largest in the world after China. Barring China, America and Russia, in numerical terms India’s urban population is higher than the total urban population of all countries of the world. 30 per cent of the India’s population is living in urban areas and this 400 million people are generating two-thirds of the Gross Domestic Product (GDP) of our country and 90 per cent of the government’s revenue. Five of the most densely populated cities in the world are in India. This rapid growth of urban areas is the result of two factors; natural increase in population (excess of births over deaths), and migrating to urban areas. Today the movement of people from rural to urban areas (internal migration) is the most significant. It has been estimated by 2020, 140 million people will be migrating to the urban areas and it will reach to 700 million by 2050.