My research mainly focuses on how graph theory can be used to improve our tools to analyze large-scale interaction networks. For partitioning and hierarchizing networks, I have successively used metrics on graphs, spectral graph analysis, combinatorial properties of some classes of graphs, and simplicial topology of clique complexes. I take part and I promote interdisciplinary cooperation of mathematicians with other domains of science. After having worked with neuroscientists for modelling real neuronal networks, I have developed cooperation for more than fifteen years in the field of social network analysis with historians, linguists, geographers or anthropologists. More recently, I was interested in complexity science,  particularly in complex networks and about the links between local and global properties.

I have been director of The Toulouse Social Sciences and Humanities Research Institute during 6 years, Scientific Deputy Director for 5 years at the CNRS Institute for Social Sciences and Humanities and President of the french National Network of Social Science and Humanity Centers during 2 years.

I have lead a project for a Toulouse Institute for Complex Systems Studies.