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Collision avoidance on large transport aircraft involves many components: Air Traffic Control (ATC), the pilot, and the Traffic alert and Collision Avoidance System (TCAS). This research explores pilots’ interactions with ATC, the environment, and TCAS. Collision avoidance reports from NASA’s Aviation Safety Reporting System (ASRS) were used to examine the encounter conditions surrounding collision avoidance incidents, including airspace, environment, and type of aircraft involved as well as pilot perceptions of the event. A coding scheme, developed in the early stages of this research, captured details regarding the traffic encounter, the role that ATC and TCAS played within the encounter, and the flight crew’s response. This analysis spanned TCAS-related ASRS incident reports from 2008 to 2010. The results illustrate that the availability and presentation of traffic information impact pilot agreement (and disagreement) as well as their compliance (and noncompliance) with ATC and TCAS issue maneuvers.