The problem of infertility, with particular reference to Africa south of the Sahara, is reviewed. In many areas, up to 40% of women are reported to have completed their reproductive years without bearing a child. The condition is widely distributed, but also often localized in pockets corresponding to geographical or tribal units. Most available demographic data provide estimates of childlessness but it is not sufficient to define the problem in terms of primary and secondary infertility, pregnancy wastage, and infant and child mortality. The major underlying cause for the high levels of infertility appears to be the sequelae of Neisseria gonorrhoeae infection in both men and women, manifested as obstructive azoospermia and tubal occlusion. Other infections, such as those that may follow abortion or delivery, or systemic infections, may be important in some areas. The available data suggest that different patterns of infertility and pregnancy wastage, and different etiological agents and processes, contribute to the problem of infertility in the different areas. The need for a systematic, standardized research approach in several areas is clearly indicated.