Céline Rozenblat researches are widely directed on the relations between evolutions of powers and values and networks dynamics into systems of territories. In order to develop these topics in a comparative point of view, she built many large database on European cities and on networks since 1987. In particular, the question of comparizon was extremely delicate for European cities and she produced with Pumain and St-Julien, Cattan "the concept of cities in Europe" for Eurostat (1991). She built since 1990 representative database on located multinational firms networks leading her to deal with territorial dynamics and actors' strategies in the same time. This duality obliged her to rethink multi-level approaches in geography, largely inspired by sociology of networks and physics. Diachronical and dynamic studies supply materials to develop spatial and dynamic models, simulations and vizualisations.