One response to global crisis is the decision to migrate or attempt to seek refuge across national borders, in many cases without authorisation and without the necessary travel documents. Currently, a global trend of south-north irregular migration can be observed, especially strong in present cross-Mediterranean migration. Attempts to map transit migration in the Mediterranean area identify typical routes in the west (between Morocco and Spain), in the centre (between Libya and Italy) and in the east (between Turkey and Greece). Whereas these typical routes of clandestine migration across the Mediterranean Sea are quite well documented, a clearer understanding of the social dimension of this irregular transit migration is still lacking. Little is known about the social profile of irregular migrants arriving at various European shores, of their gender or age composition, their motives for migrating and especially their often traumatic experiences of clandestine border crossing. Furthermore, the political responses of the nation-states involved might vary over time in relation to increasing numbers of undocumented migrants arriving at or passing through their national territory. By narrowing down the focus of analysis to a specific geopolitical region (here the Mediterranean basin), our understanding of the phenomenon of irregular migration can be contextualized and deepened by a comparative approach. The workshop calls for empirically based research on Mediterranean transit migration which aims at a better understanding of what has been labelled as 'mixed migration flow' in Europe.