Since September 11, 2001, the pressure on Al Qaeda has increased. Training sanctuaries and havens have been eliminated, and numerous fighters of the organisation have been killed, captured or are in hiding. Today, Al Qaeda can be understood -- according to many analysts -- much more as an ideological platform than an operative terror organisation: Bin Laden and al-Zawahiri cannot provide tactical leadership. But they pose a new, more virtual threat insofar as recruitment, training and indoctrination, as well as propaganda, have moved to small cell operations in virtually every country, under the Al Qaeda ideological banner. The stark fact is that the execution of the global war on terrorism has not decreased international terrorism directed against the West. In view of this apparent failure of present strategies, the editors have sought the opinions of eight distinguished scholars and experts in the field to reflect on the following questions: What additional actions are required in counter-terrorism policy to reverse the increase in terror-directed activities? What are the main shortcomings of current policy initiatives? And, what policy recommendations can they make as a result of recent developments in counter-terrorism theory and new data on terror perpetrators and incidents? Their answers set out in this volume provide important contributions -- academic, scientific, and practical -- to the debate on how to effectively counter terrorism, which methods to pursue, and which means to apply. The volume is structured in three parts: Possible anticipatory actions in the context of counter-terrorism and prevention; the question of reasonable reaction to a perceived or real threat; and discussion on the effects of an attack and how to deal with them.