This case study was carried out in the framework of the second work package (influence of local actors on national decision-making processes) of the European research project COWAM 2. The study aims at identifying and analysing the strategies and influence mechanisms implemented by the local actors of Dunkirk in order to influence the process of elaboration of the 30th July Law on the prevention of natural and technological risks. This case study was carried out using, on the one hand, a desk study and, on the other hand, a participative methodology involving a working group.