Migration flows are one of the reflections of inequalities in the world, between North and South, between cities themselves and within them. This chapter discusses the links that exist and are constantly being renewed between city networks and migratory networks. It focuses on few examples of urban forms taken in various parts of the world, fuelled by migratory flows, in particular in Asia, the Arab world and Africa. Since the 1980s, the notions of migratory field or circulatory territory have made it possible to highlight continuities rather than ruptures and to pose the question of the link between migratory flows and urban spaces differently. The chapter focuses on two well-known migratory situations in order to understand their evolution over the past half-century: the Maghreb migratory field and migration in sub-Saharan Africa.