KHAT IS A QUASI-LEGAL PSYCHOACTIVE SHRUB, produced and marketed in the province of Harerge, Ethiopia, and widely consumed throughout Northeast Africa. In the late nineteenth century the main cash crop of Harerge was coffee. Leaf of Allah examines why farming families shifted from cultivating coffee and food crops to growing khat. Demographic, market, and political factors facilitated the emergence of khat as Harerge's leading agricultural commodity. This development increased the scale of unofficial cross-border trade in consumer goods. This study explores the consequences of the new cash crop for the regional economy as a whole, for farmer-state relations, for the nature and balance of local social relations, as well as for Harerge's physical, socioeconomic, and political landscapes.