This paper tests Caldwell’s mass schooling hypothesis in the context of rural Pakistan. His hypothesis was that the onset of the fertility transition is closely linked to the achievement of “mass formal schooling” of boys and girls. Punjab and Northwest Frontier Province (NWFP) were selected for this study because they appear to be on the leading edge of the demographic transition-a transition that has only recently begun-as suggested by rapid recent increases in contraceptive practice. The study covered a range of rural villages or communities with very different socioeconomic and schooling conditions in order to examine the effects of both school access and quality on family-building behavior in Pakistan. The study concludes that gender equity in the schooling environment, as measured by the number of public primary schools for girls in the community or by the ratio of the number of girls’ schools to boys’ schools, has a statistically significant effect on the probability that a woman will express a desire to stop childbearing and, by extension, on the probability that she will operationalize those desires by practicing contraception. Indeed, the achievement of gender equity in primary school access in rural Punjab and NWFP could lead to a 14-15 percentage point rise in contraceptive use in villages where no girls’ public primary school currently exists and an 8 percentage point rise in villages with one primary school for girls. This is entirely supportive of the Caldwell argument that mass schooling is an important determinant of fertility change, particularly when girls are included. It would appear that fertility change will be much more difficult and will come much more slowly when girls are left behind