Re-linking is research in progress. It is a comparative research about young people in Paris and Madrid disadvantaged neighborhoods. The aim of this project is to understand the type of networks that help (or limit) youth’s social mobility. Two suburbs in Paris and two in Madrid have been chosen to examine the role of local networks (the family, the ethnic community and civil associations) on young people’s lives. In October 2013, I was integrated in a local community in Paris through civil and ethnic associations. The goal of this approach was to get as close as possible to the families and youths in order to know the paths of children of immigrants from Magreb and Sahel. Since May 2014, I have been developing the same approach in the suburbs of Madrid, adding the life trajectories of youths from Latin-American origin.