Studies to evaluate use-effectiveness and cost-effectiveness of natural family planning (NFP) were conducted in Liberia and Zambia. The Liberian programme provided uni-purpose NFP services to 1055 clients mainly in rural areas; the Zambian programme provided NFP services integrated with MCH to 2709 clients predominantly in urban areas. The one-year life table continuation and unplanned pregnancy rates were 78-9 and 4-3 per 100 woman-years in Liberia, compared to 71-2 and 8-9 in Zambia. However, high rates of loss to follow-up mandate caution in interpretation of these results, especially in Zambia. More women progressed to autonomous NFP use in Liberia (58%) than in Zambia (35-3%). However, programme costs per couple-year protection were lower in Zambia (USS25-7) than in Liberia (US$47-1). Costs per coupleyear protection were higher during learning than autonomy, and declined over time. These studies suggest that NFP programmes can achieve acceptable use-and cost-effectiveness in Africa.