Because today’s security challenges require facilities to do more than deter adversaries or detect them as they penetrate fences, Sandia developed “beyond-the-perimeter” sensor and assessment defense systems. Virtual Presence and Extended Defense (VPED) systems provide reliable information to responders as early and as quickly as possible to create detection zones and video assessments where none previously existed along such potential avenues of approach as roads, trails, or ravines. VPED was installed as a pilot system to assess detection probabilities, adapting to the environment, and nuisance-alarm rates.