In this presentation, I will focus on “bidonvilles” (slums), a residential experience known by many migrants arriving in France in the 1960's. Since bidonvilles have recently known a renewal with the arrival of migrants from Romania and Bulgaria, it seems relevant to look at the biographical consequences of such an experience of marginality for the previous "children of bidonvilles", namely people of migrant origin who spent a significant period of their youth time in slums. To do so, I will analyze the effects of three main factors: • familial strategies and trajectories, anterior and posterior to the bidonvilles experience • national and local political contexts • contemporary patterns of sociability in their interplay with memory dynamics In this perspective, I will distinguish between three types of trajectories and memories, drawing the boundaries of three distinct groups. For some migrants, living in slums had little consequences on their later lives, while for others, it had long lasting and negative ones. For a last group, bidonvilles’experience seems to have had short but nonetheless negative consequences. For each of these groups, I will describe and analyze the effects of this residential experience, looking at both patterns of trajectories and memories. Empirical materials are from an ongoing PhD research in the cities of Nanterre and Champigny-sur-Marne, that both hosted bidonvilles after the Second World War. It includes in-depth interviews with 60 previous inhabitants from Portuguese and Algerian/Moroccan origins, ethnographic data and various written sources analyses.