European integration is for its essential part reflected in the building of urban networks that are increasing interdependencies between cities. Evidence of this process is brought through the observation of a variety of networks whose nodes are located in cities, especially the development of international functions. Analysis of airlines networks (2000) as well as the economic linkages between multinational firms (1990,1996) provide a good illustration reflecting the dominant features of such a process (Rozenblat, 1993, 1997, Amiel, 2003). But other international networks as those created by cultural or scientific activities introduce may have distinctive patterns compared to the previous ones (Rozenblat, Cicille, 2003). From these analyses, four major modes can be identified in the spatial construction of urban networks in Europe (ESPON, 2003): 1) integration according to the urban hierarchy at the European scale 2) integration according to a national urban hierarchy 3) integration according to border and regional effects 4) integration through functional specialisation We will demonstrate to which extent each integration mode is effective in the set of urban networks that we analyse. Second, we shall try to show how the four modes are interacting by analysing their variations in space and time.