This paper attempts to prove that the rate of population growth in the Kiangnan region during the early years of the mid-Ch'ing dynasty was not only slower than that of other regions of China at that time, but also slower than that of the Kiangnan region during the Ming. A number of population control methods caused this slow growth rate (which helped maintain the individual prosperity), not the usually-cited factors of war and natural calamities such as floods and epidemics. Such methods included infanticide, encouragement of bachelorhood and spinsterhood, restrictions on marriage, late marriage, abortion and birth control. In addition, the geographic mobility of young and middle-aged males decreased the opportunities for pregnancy during marriage. This paper also shows that even in a society such as that of the Kiangnan region during the mid-Ch'ing, in which modern ideas relating to birth and fertility, as well as modern birth control techniques, had yet to be introduced, the people utilized various techniques to slow the growth rate of the local population. This in turn led to a complementary relationship between economic and population growth rates.