Drive a few miles from the centre of Accra, the capital of Ghana, into the neat rows of houses that surround it and the paved roads disappear almost as quickly as the phone lines. Yet this has not dented the ambitions of Kwami Williams, a graduate of the Massachusetts Institute of Technology (MIT) who is building a business processing moringa trees and exporting the resulting tea and cosmetic oils. Before mobile-phone usage exploded across Africa, starting a venture such as this on a shoestring would have been impossible—the costs of communicating with the thousands of smallholders who grow the trees would have been prohibitive. Now this business supports some 1,500 farmers.