Terrorism has changed. New terrorist ideologies have been accompanied by new methodologies - weapons that are harder to detect and suicide tactics that are much harder to protect against than the 'old' terrorists.
But what does our immediate future hold? And how well prepared are we to confront it?
Frank Barnaby looks at the new weapons and tactics available to today and tomorrow's terrorists, including 'dirty bombs', liquid explosives, and cyber-terror, which can wreak havoc with nothing more specialist than a laptop.
In examining terrorism past, present and future Barnaby shows how we have come to our present situation and reviews the limits of counter-terrorism.