Our world is characterized by ever-changing threats to critical facilities, national assets and international interests. Understanding these threats and how they affect the design of facilities for security continues to be a leadership area for ORNL. Traditional approaches involve simple adversary timelines and delay measures that allow for interdiction by response forces before the adversary can reach the target. ORNL can and does contribute in this approach through training and other exercises, both locally and abroad. ORNL is interested, however in a larger view of vulnerability as well that takes into account issues such as system maintenance, training, organizational analyses, and human reliability concerns. This broader view promotes the development of "living" programs that can monitor and anticipate changes in threat and accommodate those changes in system or facility design. In this way, an established level of protection can be sustained and more robust solutions are implemented for the customer.