Pakistan with an estimated population of around 142.5 million in mid 2001 is the seventh most populous country in the world and fourth in Asia and Pacific countries. The historical trends indicate a continuously increasing growth in population (Table 1). The population of the area now constituting Pakistan was 16.6 million in 1901. Since then the population has increased over eight-fold. Annual growth rates have risen from 1 percent in the first three decades of the century to around 2 percent in the next three decades and after peaking at little over 3 percent in the 1960s, has started showing a declining trend. Currently it is estimated that Pakistan’s population is growing at around 2.1 percent, still a very high rate of annual growth in population. Major contributing factor to the fast growth in population of Pakistan has been high fertility which has remained high for a very long period. It is evident that nearly 100 million population has been added to the population of Pakistan since 1961, that is, during the last four decades. Such rapid growth in population has several adverse implications for the socio-economic development of the country which has been offsetting the gains in social and economic development.