The process begins with the selection of the assets that are most in need of protection. The next steps are to determine the aggressor's characteristics, analyze the attractiveness of an asset to an aggressor, identify potential modes of attack, and decide on appropriate countermeasures. The process should also include an assessment of existing protective measures and considerations of constraints on the design solution. The decisions should also rest on awareness of terrorist dynamics and of the need to develop a fully integrated security system that provides diversity, redundancy, and collective resource management. Figure. (Author abstract modified)