gain, comprehend and process the SA that is coming in to the operator, both general background SA and the SA specifically related to the decision. In other words, if everything is going OK the level of SA you have is not as critical as it is when something unusual happens or something goes wrong. Research into the decision making process is an increasing area of interest and the identification of this type of relationship has led to the development of at least one integrated conceptual framework (developed by K. Tara Smith) that attempts to accommodate all of the impactors on the decision-making process, defining how they impact on the individual's ability to acquire their SA. This involves aligning the terms and concepts used by different research areas, so that the causal relationships can be identified and defined. This approach of integrating situation awareness, workload, signal processing theory, decision theory, etc. tends to subtly change the questions that are asked during the analysis process from quantifying and qualifying the SA to measures of the probabilistic aspects of a decision, such as the number of interrelationships, the certainty and time-lag of the information arriving, risk to desired outcome or effect, etc., together with the processing aspects, to do with the number of signals, accuracy and completeness of the information and importance to the operational context. In other words, instead of asking does a modification to the system provide more SA, we are asking does this modification to the system provide more SA in a form that can be used at the time when it is needed? Measurement While the SA construct has been widely researched, the multivariate nature of SA poses a considerable challenge to its quantification and measurement. In general, techniques vary in terms of direct measurement of SA (e.g., objective real-time probes or subjective questionnaires assessing perceived SA) or methods that infer SA based on operator behavior or performance. Direct measures are typically considered to be "product-oriented" in that these techniques assess an SA outcome; inferred measures are considered to be "process-oriented," focusing on the underlying processes or mechanisms required to achieve SA. These SA measurement approaches are further described next. Objective measures Objective measures directly assess SA by comparing an individual's perceptions of the situation or environment to some "ground truth" reality. Specifically, objective measures collect data from the individual on his or her perceptions of the situation and