Hausa control of long-distance trade in kola and cattle in Nigeria has required the formation of a network of highly stable Hausa communities in the towns and villages ofYorubaland. In the face of fierce and continuous competition by Y oruba traders, much of the success of the Hausa depended on the rapidity with which they could establish and develop these communities. This has involved various kinds of mobility of population through which continual demographic adjustments in the age, sex, and occupational structures of the communities have been made. Different Hausa traditional customs and institutions were closely interconnected with these demographic processes.