Karachi is not just a city. It is a unique city in many ways. To begin with, it is a metropolis in the strict sense of the word, characterized by an accelerating rate of suburban growth. Its rate of growth has been phenomenal, particularly since the emergence of Pakistan. From a medium-size city of less than 500,000 population in 1947 it grew to well over five million in 1981 and, according to most conservative estimates, has now exceeded 6.5 million mark. With increase in population there has been simultaneous increase in its a real extent, as indicated by the figures - 233 sq. Ian. in 1947 to 1300 sq. Km. in 1986.

Like any other major metropolitan center, Karachi is inhabited by a wide variety of communities belonging to different religious and linguistic groups drawn from different parts of Pakistan. Aside from Urdu-speaking n-migrants (Muhajirs) who still form the biggest ethnic group, there are considerable number of people from N.W.F.P, Kashmir, Punjab, Baluchistan, and of course from different parts of Sind of which it is the capital city. In this way Karachi like other leading cities of the. world has developed into a National Metropolis. No wonder, it is often described as miniature Pakistan, which is really is, just as Bombay is mini-India, London is mini-England, and Paris is mini-France.

Related with multi-ethnic character of Karachi's population is the appalling rate of massive in-migration of people from different parts of Pakistan, especially, the two northern provinces. it has been estimated that each year a new city of about 300,000 population is added to Karachi, through the process of massive inflow of people from different parts of Pakistan. As a consequence the city suffers from a chronic shortage of dwelling units, water supply, public transport, and civic amenities such as schools, hospitals , parks and playgrounds, etc. Over and above, is the shortage of jobs in both public and private sectors.

The shortage of dwelling units, a consequence of massive immigration, has been largely responsible for the emergence of squatter settlements or Katchi Abadis. The number of Katchi Abadis in the city increased from 51 in 1948 to 212 in 1959, 362 in 1978 and-438 in 1987. About 2.3 million people or one-third of the total population resides in these Katchi Abadis of Karachi. At this rate, it is quite likely that by the year 2000 A.D. not less than half of the total population of Karachi would be living in Katchi Abadis.

The city is confronted with yet another serious problem related with the existing intra-city transportation system, which is under heavy strain. The chief contributing factor is the explosive growth of its population due mainly to massive migration.. Added to this is the ever-increasing number of people who visit the city daily ,on a business trip on a social call.