The forced removal of irregular migrants has become a central part of European immigration policies. Although legally defined as a measure of last resort, in practice, administrative immigration detention is a key instrument to facilitate the forced removal of irregular migrants. Scarce international criminological research illustrates the hybrid nature of immigration detention: although administrative in character as an instrument of migration control, it contains punitive elements turning it into a ‘prison-like’ institution. In order to gain insight in its nature and the implications for those involved, theoretical and empirical research on immigration detention in Belgium is needed. This research, on the cross-section between penology and migration studies, aims to fill this gap by studying the organisation of forced removal and daily life in immigration detention. In order to fully understand forced removal practices, multiple viewpoints will be taken into account as both the perspective of irregular migrants subjected to immigration detention and the perspective of different immigration detention staff members (governors, educators, social workers and security personnel) will be studied. Extensive ethnographic fieldwork will be carried out in two immigration detention centres and a multimethod design including observations, in-depth interviews with migrants subjected to immigration detention and focus groups with staff members will be used to meet our research goal.