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The inclusion of situation awareness (SA) as a crucial component in many naturalistic decision models emphasizes the criticality of SA to the decision process (e.g., Connolly, 1982; Klein, 1993a; Lipshitz, 1993). Situation aware-ness can be defined as “the perception of the elements in the environment within a volume of time and space [Level 1 SA], the comprehen-sion of their meaning [Level 2 SA], and the projection of their status in the near future [Level 3 SA] ” (Endsley, 1988). Although deci-sion quality and SA are not synonymous (a per-son who has poor SA can still make a good decision, if only by luck), poor SA degrades the decision process. In situations in which actio