Uncertainty, complexity, and rapid change will increasingly characterize humanitarian threats in the foreseeable future. These threats may range from the prospect of the 320-meter asteroid 99942 Apophis crashing into the Pacific rim in 2035 to Himalayan snow meltdown that would leave an estimated 300 million South Asians without water. Regardless of the particular event, the effects of such potential catastrophes are essential but almost too cataclysmic to contemplate.