This volume contains the results of the Bayreuth SFB research program "Effects of globalisation processes on the vitality of languages in West African cities". Two towns with different historical and colonial background, Maiduguri in Nigeria and Banfora in Burkina Faso, were selected as research areas. The contrast between language and social institutions is most obvious in the colonial and post- colonial world in Africa. Colonization was characterized by the importation of European institutions which were of a qualitatively new nature linked to the globalising forces. This qualitative newness is captured in our term "direct globalisation". A basic observation is that the globalising forces led to a hierarchicalisation of languages in Africa which is not obviously attested in the institutions of direct globalisation. Our term "indirect globalisation" describes the alignment of local practices to the external forces and institutions introduced during a globalising colonial and post-colonial experience.