Capacity development has a prominent place in international as well as in Dutch development cooperation. In order to be able to choose and follow their own development paths, developing countries need appropriate and adequate capacities. The substantial amount of support provided by the international donor community, however, has not yet resulted in sufficient capacity. This is particularly the case for capacity geared to poverty reduction. To gain a better understanding of how and under what circumstances capacity development support can be effective, this evaluation focuses on learning, and identifies factors that explain the achieved level of effectiveness.