Doubtlessly, modern technology has radically altered the surveillance process. What it has not done, however, is render physical pre-operational surveillance obsolete. Despite innovative Internet tools, a person sitting in an Internet cafe in Quetta, Pakistan, cannot get everything he or she needs to plan and execute a terrorist attack in New York. There are still many things that can only be seen in person, making eyes-on surveillance vital to pre-operational planning. And, as long as actual physical surveillance is required, countersurveillance will remain a key tool for proactively preventing terrorist attacks.