As the army undergoes its planned transformation, it will rely more and more on humans interacting with complex visual displays. As the complexity of those systems increases, so also does the possibility that important changes in visually presented information will be missed. Research on change detection suggests that people often fail to notice changes in visual displays when they occur at the same time as various forms of visual transients, such as eye blinks or screen flashes, or scene relocation. In this experiment, we investigated change detection using the Force XXI Battle Command, Brigade, and Below display, with no more than 2 map icons ever depicted at one time. Participants were instructed to monitor the display and report changes they noticed as quickly as possible. They were also periodically instructed to conduct certain tasks with the system, such as performing a circular-line-of-sight analysis (CLOS). Changes scheduled for observation included icon appearance and disappearance, changes in icon platform, color/affiliation, or position. We analyzed the observer's ability to detect these different types of changes, as well as the effect of performing concurrent tasks (such as the CLOS) on change detection. Our dependent measures were speed and probability of change detection. Observers were very good at detecting icon appearance, disappearance and color changes; however, they missed more than 20% of the platform changes. Detection of icon movement was dependent on the length of movement, with detection being particularly poor (more than 25% misses) when the icon was in the periphery of the map and the distance moved was small. There was a dramatic effect of performing a concurrent task. When an icon changed simultaneously with the conclusion of a concurrent task, detection dropped to less than 50%. Possible training or design solutions to overcome this type of detection failure need to be considered as the army transforms to the Future Combat System. For example, inclusion of a dedicated change detection tool could explicitly provide operators with changes that occurred during an interruption, and would greatly assist recovery of situation awareness. Instead of an operator needing to figure out what changed, the system should provide that information.