In 2003, the northeastern U.S. suffered the largest power blackout in the nation's history. For two days, 50 million subscribers in eight states and parts of Ontario lost power, resulting in an estimated $6 billion in economic losses. The primary cause of the outage: an inability to recognize, assess, and understand the inadequacies and deterioration of parts of the power grid over wide areas, a story not unfamiliar to critical infrastructure management. From reputation damage and expensive penalties to direct financial losses into the billions of dollars, network reliability at the critical infrastructure level was (and still is) a top concern in the utilities industry.