The links between security, terrorism, and globalization were highlighted vividly by the Sept. 11, 2001 attacks on New York City and Washington, D.C. The hijackers were non-US nationals who worked in the US and even studied to be pilots there - enjoying the mobility and opportunities afforded by globalization. The spread of destabilizing weapons and delivery systems through commercial transactions also demonstrates the dark side of economic integration. But the global reach of terrorist groups has led to the emergence of global cooperation in counter-terrorism. The following articles have been assembled to shed light on these and other related issues.