Africa has recently known dramatic urban growth, which is good news if urbanization drives growth. Yet, the agglomeration effects story was built on manufacturing, a ”missing” sector in Africa. I develop a structural transformation model where primary exports (cash crops, mining) push urbanization, through a rise of the nontradable service sector. This gives rise to consumption cities where spillover effects are lower than in production cities, thus questioning the link between urbanization and growth. I illustrate this model with a case study on cocoa production and
cities in Ivory Coast and Ghana, two highly urbanized African countries. Combining decadal district-level data on cocoa production and cities from 1901 to 2000, I document how cities follow the cocoa front, using the fact that cocoa is a migrant culture as an identification strategy. I find that cocoa production launches a self-reinforcing urbanization process. I give evidence for the channels behind this relationship, emphasizing consumption linkages. I show that the employment structure of those cities might prevent them from being engines of growth.