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In aviation, many actions are taken to reduce risk. However, not all risks can be avoided. To effectively manage risk, managers and regulators must evaluate and compare risks associated with different threats. Yet, it is frequently difficult to obtain reasonable assessments of these risks. Traditional approaches often produce unsatisfactory results when the probability of failure is low but the costs of failure are high -- as is often the case in modern civil aviation. Attempts to use a single dimension to evaluate threats often lead to unreliable and contentious assessments. Many risk assessment heuristics and displays can yield misleading and sometimes mathematically incongruous assessments. Furthermore, increases in costs caused by people’s reactions to failures are often ignored or grossly underestimated. In this paper, problems with risk assessment in aviation are discussed and a Tool for Risk Identification, Assessment, and Display (TRIAD) designed to address many of these problems is described.