This volume exemplifies the general theory of a field of professionals of security and proposes a map of the European internal security agencies (Europol, Eurojust, Frontex, OLAF). It insists on the relations between the agencies in order to give a better idea of the flow of communication and strategic or operational decisions produced at the EU level as too often the audience has only monographers about these agencies. Any person interested in security in the EU will thus have a better idea of the relations between the agencies.
