On 14 June, the Schengen zone will celebrate its 25th anniversary with its 25 members. Initiated by five EU founding countries – France, Belgium, Germany, Luxembourg and the Netherlands – this abolition of controls at internal borders is doubtless the most tangible materialisation of the European principle of free movement. More than 400 million citizens do not need to show their passports when they travel in this growing area, even if they need to have an identity card in case of a police control.

Two EU states have not joined (the United Kingdom and Ireland), but on the other hand three non-EU states - Switzerland, Norway and Iceland - are part of the Schengen area. Bulgaria, Romania and Cyprus are expected to follow soon. “This freedom to travel must be matched with greater responsibilities,” notes Commissioner Cecilia Malmström. Indeed, organised crime and terrorist activities also find advantages in a border-free area.

The paradox of Schengen is that the area is also associated with a ‘nightmarish’ subject for its home affairs ministers: the ongoing absence of a modernised Schengen Information System (SIS II), to adapt to 25 member countries and more. In spite of six years spent on the project and 55 million euro in funding from the EU budget so far, SIS II is still on the drawing board.