The United States of America changed with the coordinated terrorist attacks that resulted in the destruction of the World Trade Center, damage to the Pentagon, and the crash of an aircraft in the State of Pennsylvania. The people suddenly felt insecure. The question lingered in their minds, when and from where will the next attack occur? Terrorist attacks are sudden and unexpected. Even if we have some information on a possible attack, we will generally not know exactly where, when, or how an attack will occur. Without specific information, the most effective strategy is to plan in advance to prevent and mitigate, where possible, and to respond when necessary with flexibility, coordination, and speed. Given these imperatives the first step is to find or develop a methodology that can be used by Alabama transportation officials to produce a prioritized list of the most critical and most vulnerable highway infrastructure that needs to be protected.