Given the expanding vulnerability of human populations and natural systems, management professionals are ever more frequently called upon to apply natural hazard modeling in decision support. When scientists enter into predictive services, they share professional, moral, legal, and ethical responsibilities to account for the uncertainties inherent in predictions. Where hazard predictions are flawed, limited resources may be unjustifiably be spent in the wrong locations, property may be lost, already stressed ecosystems may be critically damaged, and potentially avoidable loss of human life may occur. These essential concerns for reliable decision support compel thorough characterization of the uncertainties inherent in predictive models.