This chapter questions the foundations for a general theory of borders, which could be categorized in terms of permeability according to state capacity, state intentions and the character of the mobile subject. Rather than use macro-theories of migration, this model arises from a concern with the micro-politics of border control, illustrated by an individualistic focus. Starting from the site of the airport, the anthropological model of the ‘rite of passage’ is applied to modern borders – separating crossings into pre-liminal, liminal, and post-liminal rites – which are shaped by architecture, the confessionary complex and hyper-documentation. The interface between state policies and discourses of border security and the practise or capacity of state policing is much under-theorized and understudied. These questions have taken on an accelerated salience since 9/11. I would argue that there has been no deep-structural change to the process of crossing borders since the terror attacks. But, the amount of public attention and policy scrutiny has increased.