Acquiring a human target through an electro-optical sensor is of great interest to a variety of governmental agencies. However, relatively little field data collection had been focused in this area, so that there remained some uncertainty in the correct choice of modeling parameters. The Night Vision range performance modeling methodology can accommodate this unique target in addition to the more conventional tactical vehicle. Recent experiments at the NVEOD in human target detection have provided insight into the task involved and the system modeling requirements. This paper recounts the results of two experiments involving personnel target detection with FLIRs. The first experiment involved first generation TOW night sights in a ground-to-ground scenario and the second experiment involved two different airborne FLIRs, one parallel and one serial scan, in an air-to-ground scenario. In both experiments the targets included walking and standing men. The ACQUIRE model was exercised against the test results to determine the appropriate values to be used for the characteristic dimension and task cycle criteria for moving and stationary personnel targets in a non-search scenario. Additional theoretical discussion in the paper explores static performance and search concepts in relation to motion and detection.