The overall aim of the proposed project is to develop a comprehensive approach to prevent and counter violent radicalisation and extremism. The PERICLES (Policy recommendation and im-proved communication tools for law enforcement and security agencies preventing violent radicali-sation) project is especially dedicated to transitional processes of radicalisation. To meet its aims, PERICLES will consider violent left-wing and right-wing as well as religious ideologies. A special focus will be set on the risks connected with digital violent propaganda. The PERICLES project will deliver advanced and validated counter-propaganda techniques that are target-group-specific. Furthermore, the cooperation between relevant authorities who have due regard against violent rad-icalisation or support the process of de-radicalisation will be enhanced through the use of the project outputs. The comprehensive PERICLES prevention strategy will therefore largely address law enforcement agencies (LEAs) and security agencies; but will also find use by prisons and social workers, teachers and even relatives of affected people.