Since September 2001, the U.S. has increased focus on radical Islamist and terrorist groups in Southeast Asia, particularly those in the Philippines, Indonesia, Malaysia, Thailand, and Singapore. Al Qaeda penetrated the region by establishing local cells, training Southeast Asians in its camps in Afghanistan, and by financing and co-operating with indigenous radical Islamist groups. To combat the threat, the U.S. has pressed countries in the region to arrest suspected terrorist individuals and organisations, funded and trained Indonesia's elite counter-terrorist unit, and deployed troops to the southern Philippines to advise Philippine military in their fight against the violent Abu Sayyaf Group. This book examines the rise of Islamist militancy and terrorism in the region, its background and issues, and options for U.S. policy.