Introduction : Les nouveaux mondes des migrations et des territoires

This article is a general introduction to the special issue of the ASRDLF symposium held in Martinique in 2011. It attempts to explain the reasons why a strong attention is being paid to migrations while international or long distance migrations are a profound and permanent reality. Wars, poverty, ethnic conflicts, climate change have widely determined the tenure of space, have structured the lifestyles, job searches and incomes etc. The ongoing processes are resolutely linked to the extent of movements, to the trade liberalization, to the contemporary crisis and to the weakening of the welfare state. The imperatives of efficiency have also intensely affected the territories - especially the urban ones -, a fact that leads to new components of brain drain and to increase poverty belts. Conceptualizing and formalizing the representations of migratory phenomenon are then required.