Urbanization-desertification interactions in the arid zones of the Sudan represent a challenge for future management planners. Desertification leads to a considerable movement into the towns, thereby encouraging the urbanization process. However, due to the large pull effect of large urban centres which are limited in number and unevenly distributed over the area, most of the migration is oriented towards them. This tendency is strengthened, furthermore, by the present planning trends of growth pole centres. The result is overcrowding, negative over-urbanization diseconomies and more pressure on the natural resources in the immediate hinterland, thus further accelerating the desertification process. Some examples are given in the paper to show how the rapid increase of urban population and the rapid growth of urban centres have reflected themselves in difficulties in procuring wood fuel or naturally grown raw materials for traditional and small urban industries. The specific example of Khartoum, the largest urban centre in the Sudan with the highest rate of growth is treated in detail to show how rapid urbanization processes would result in intensified desert conditions and how ecological interactions and effects would be faster and more serious in a more vulnerable ecological location.