Special Economic Zones (SEZs) are an increasingly popular instrument of trade and industrial policy, particularly in developing countries. The authors present the (socio-)economic effects of SEZs through an analysis of existing literature. One focus is on SEZs in Africa. This shows that the hope for SEZ-supported growth, as in Asia, has largely not been fulfilled in Africa. The authors recommend that the „Deutsche Gesellschaft für Internationale Zusammenarbeit“ (GIZ) should expand its fields of activity accordingly in view of the increasing number of SEZs in developing countries. They see a need for further research on the topic of SEZs in order to better understand their effects, success factors and the controllability of SEZs.