In Sub-Saharan Africa there has been a steady rate of urbanization. First, there are the large burgeoning cities which are in most cases industrial, commercial and administrative centers with a population ranging between 500,000 to 3,000,000 or more. Second, there are cities with populations between 100,000 and 500,000. Some have industrial, commercial and administrative activities. Third, there are medium sized towns with a populations between 20,000 and 100,000. Some are district or provincial centers. Fourth, there are small sized towns with populations below 20,000 which are dotted in the countryside.
In terms of urban studies, the first and second categories usually attract the attention of scholars (Mabogunje 1980; 1968; Coquery-Vidrovich 1991; Okafor 1988, 253-63). The third and fourth categories are left out as being insignificant in terms of urbanization, population size, commercial activity and administrative importance. They are lowly rated in terms of importance to urban studies.
Although they vary in size and population, small- and medium-sized towns play similar and crucial roles in the economic, social and political development of the areas in which they are located. They serve as links between the urban centers and the rural countryside. They also act as centers of innovation and diffusion of ideas from the urban areas to the countryside and vice-versa. From the urban point of view, small- and medium-sized towns are seen and treated as forward bases for the domination of the countryside. In the rural view, they are seen and treated as either markets or distribution centers at which the produce of rural areas are collected, marketed and absorbed in the local, regional or export market economy. In short, they are seen as points at which capitalist and peasant economies meet and co-exist.