Foggy social structures

European countries are currently involved in several irregular migration systems, resulting in undocumented populations estimated at several millions. They manage to live and work for years without a certified identity -- a phenomenon that challenges existing notions of political statehood and societal membership. Drawing on empirical studies carried out in a variety of settings, the authors of this illuminating study analyse the ways in which such irregular migration systems developed over time, interacting with changes in European labour markets, welfare regimes and immigration policies.