Resilience is defined in the Oxford English Dictionary as "The action or an act of rebounding or springing back; rebound, recoil." or "Elasticity; the power of resuming an original shape or position after compression, bending, etc."   The concept of ecological reslience was described by C.S. Holling in 1973 as "a measure of the persistence of systems and of their ability to absorb change and disturbance and still maintain the same relationships between popUlations or state variables."  In 1998, Butte, CO, was described as a resilient city in an article in Montana: The Magazine of Western History, but one of the earliest works on the concept of resilient cities was Godshalk  in 2003, who proposed a "comprehensive strategy of urban hazard mitigation aimed at the creation of resilient cities" able to withstand both natural hazards and terrorism.