It is in the interest of the foreign national, the authority of the country of origin and the Immigration Office that the identification procedure is rapid. To avoid unnecessarily long detentions, the Immigration Office has decided to try and determine the identity and nationality of iirregularly staying third-country nationals before they are put in a detention centre for their return. This has the advantage that the identification process does not have to wait until after detention. It is then only necessary to apply for the travel document at the relevant diplomatic or consular representations.

Foreign nationals incarcerated for common law offences are placed at the disposal of the Immigration Office after they have served their sentence. The Immigration Office then makes a decision based on the residence situation of the person concerned and the potential danger that they represent to society. Since 2005, the Immigration Office has had an operational service exclusively responsible for the identification of foreign nationals detained in prison. Return coaches have been appointed for this purpose. They must persuade the irregularly staying foreign nationalto provide information about their identity and nationality. It is in the best interest of the individual to cooperate, as this may influence the decision of the sentencing court, which could grant early release based on a variety of elements, including willingness to cooperate with identification and return. The return coaches also act as intermediaries between the foreign nationals in prison and the Immigration Office. During an interview, the return coach must provide the detainee with the necessary explanations concerning their administrative situation. Therefore, to organise a quick and efficient repatriation from prison and avoid the transfer of a former detainee to a detention centre, it is essential that this person be identified before release. This is also in the interest of the foreign national so that their administrative detention is not prolonged unnecessarily after they have served their sentence.