Stimulating agricultural growth is critical to reducing poverty in Africa. Commercial agriculture, potentially a powerful driver of agricultural growth, can develop along a number of pathways. Yet many developing regions have failed to progress very far along any of these pathways. Particularly in Africa, agriculture continues to lag. During the past 30 years the competitiveness of many African export crops has declined, and Africa's dependence on imported food crops has increased. While the poor performance of African agriculture can be attributed partly to adverse agroecological conditions, experience from elsewhere in the developing world suggests that significant progress is possible. The Guinea Savannah covers some 600 million hectares in Africa, of which about 400 million can be used for agriculture. Less than ten percent of this area is currently cropped, making it one of the largest underused agricultural land reserves in the world.