The Transportation Security Administration (TSA) conducts or oversees passenger checkpoint screening at 450 federalized airports. Passenger checkpoint screening is a process by which passengers are inspected to deter, detect, and prevent explosives, incendiaries, weapons, or other security threats from entering sterile areas of an airport or getting onboard an aircraft. As threats to transportation security evolved, TSA needed a screening technology to detect nonmetallic threats. TSA developed Advanced Imaging Technology (AIT) to screen passengers for both metallic and nonmetallic threats concealed under clothing—without physical contact. In 2013, TSA equipped all AIT with Automated Target Recognition software, which displays a box around anomalies on a generic outline of a body. Our objective was to determine the effectiveness of TSA’s AIT, Automated Target Recognition software, and checkpoint screener performance in identifying and resolving anomalies and potential security threats at airport checkpoints. The compilation of the number of tests conducted, names of the test airports, and quantitative and qualitative results of our testing is classified or designated as Sensitive Security Information. We made one recommendation that when implemented should strengthen the effectiveness of identifying and resolving security threats at airport checkpoints.