The main aim of this article is to test hypotheses derived from the model for contact-induced language change as formulated in Thomason and Kaufman (1988 and Thomason (1998)). As the model correctly predicts the asymmetries between the mutual influences of the Germanic and the Romance varieties in Brussels and Strasbourg it is a very powerful tool for describing the contact patterns in these cities. The analysis shows that the contact patterns are very similar, both from a quantitative and from a qualitative point of view, despite important differences in the sociolinguistic situation of both cities. The striking similarities in the outcome of language contact seem to find a plausible explanation in the fact that the language contact situations in both cities are similar from a typological point of view: in each city a variety of French is in contact with a Germanic variety (Alsatian and Brussels Dutch). Thus, the claim of the article is that the structure of the languages plays a more prominent role in the outcome of language contact than the sociolinguistic history of the speakers.