Abstract: A very influential model of the Demographic Transition was based on the conclusion that fertility decline in Europe was due to “stopping” (terminating childbearing at younger ages) rather than “spacing” (increasing the time between births). This interpretation had important practical and policy implications, because it was linked to arguments about knowledge and acceptability of birth control. Recently, the same issue has re-emerged in research on Africa, where some observers see modern contraception being used for spacing by women who still desire large families. Evidence and interpretation have been challenged in both historical and contemporary debates, but progress has been hindered by the absence of an agreed upon measure for spacing. This presentation will present estimates from the “cure model,” a regression technique that estimates the impact of co-variates on both stopping and spacing. Comparisons will be drawn from 18th and 19th century Europe and late 20th century Africa.