This paper deals with the findings of the World Fertility Survey (WFS) and Contraceptive Prevalence Surveys (CPSs) in five areas of common interest: fertility, contraceptive use, measuring the effect of the availability of contraceptives on levels of use, the unmet need for family planning services, and breastfeeding. The comparisons have several implications for those designing surveys of fertility and family planning in developing countries, among them, that women should be asked for the dates of at least their last two births (not just the last birth as in the CPSs) in order to ensure accurate estimates of fertility and duration of breastfeeding.