The welfare of our society depends on effective assessment and management of risks to our most critical infrastructure systems. Currently fashionable probabilistic risk assessment estimates expected loss value, where the consequence of an "event" is measured in, e.g., economic replacement cost, or injuries or fatalities, as appropriate. Yet, recent examples - global financial crises, power failures, oil spills and floods - suggest we are better at building complex systems than we are at assessing potential damage from natural events or intentional actions. This presentation will describe how game theory and optimization can advise allocation of limited resources.