Situation awareness (SA) has become a widely used construct within the human factors community, the focus of considerable research over the past 25 years. This research has been used to drive the development of advanced information displays, the design of automated systems, information fusion algorithms, and new training approaches for improving SA in individuals and teams. In recent years, a number of papers criticized the Endsley model of SA on various grounds. I review those criticisms here and show them to be based on misunderstandings of the model. I also review several new models of SA, including situated SA, distributed SA, and sensemaking, in light of this discussion and show how they compare to existing models of SA in individuals and teams. Keywords: situation awareness, sensemaking, working memory, situation assessment, team situation awareness Situation awareness (SA) theory, design, train- ing, and measurement have formed a substan- tive portion of the human factors research field over the past 25 years. Although the SA con- struct was initially met with skepticism by some (Flach, 1995), the intervening years have found that SA research has taken hold in the cognitive psychology and human factors fields, forming a fundamental paradigm shift. For example, Lee, Cassano-Pinche, and Vicente (2005) examined the impact of papers published in Human Factors between 1970 and 2000. Four of the top 10 cited papers published from 1990 to 1995 were on SA, and one received 50% more cita- tions in the 5 years following its publication than any other paper published in the 30-year time period of the review. Patrick and Morgan (2010) found some 17,500 articles discussing SA in a Google Scholar search, with almost all of the papers falling after 1988 and a sharp increase following the 1995 special issue of Human Factors on SA. The interest in SA grew quickly from its initial start in aviation to many disparate fields including air traffic control, military operations, transportation, power sys- tems, law enforcement, emergency manage- ment, health care, space, transportation, education, mining, and oil and gas operations. Wickens (2008) provides an overview of sig- nificant research on SA and its progress in areas of measurement, training, error analysis, team work, automation, and workload, finding that its increased use in both theory and applications is testimony to its viability as a construct. Tenney and Pew (2006) and Durso and Gronlund (1999) also provide reviews of this popular construct. In addition, Endsley and Jones (2012) review much of the extensive research in the field and use this as a basis for a detailed process and guidelines for the design of systems to support SA and for the development of advanced train- ing programs to enhance the cognitive processes and mechanisms that underlie high levels of SA. The construct is not without its detractors, however. For example, Dekker and Hollnagel (2004) have complained that SA is a “folk model” without detail or scientific basis. Para- suraman, Sheridan, and Wickens (2008) soundly discredited that argument, showing a strong body of empirical research on the topic, its diag- nosticity with regard to human states, its pre- scriptive usefulness, and its theoretical and empirical distinction from performance and other mental constructs. 572631EDM XX X 10.1177/1555343415572631Journal of Cognitive Engineering and Decision MakingSA Misconceptions and Misunderstandings 2015 Address correspondence to Mica R. Endsley, United States Air Force, Pentagon, 4E130, Washington, DC 20330, USA, mica.r.endsley-jones.civ@mail.mil. Author(s) Note: The author(s) of this article are U.S. government employees and created the article within the scope of their employment. As a work of the U.S. federal government, the content of the article is in the public domain. Special Issue Situation Awareness Misconceptions and Misunderstandings Mica R. Endsley, United States Air Force Journal of Cognitive Engineering and Decision Making 2015, Volume 9, Number 1, March 2015, pp. 4–32 DOI: 10.1177/1555343415572631 at HFES-Human Factors and Ergonomics Society on February 25, 2015 edm.sagepub.com Downloaded from