Staff Sgt. Derek Scrivener, 11th Security Support Squadron military working dog handler, sits for a photo while waiting to complete a practice sweep with MWD Lenox the passenger terminal on Joint Base Andrews, Md., Dec. 8, 2016. MWD’s work as force multipliers, using their senses in low-visibility situations to acknowledge things a handler might not see. (U.S. Air Force photo illustration by Senior Airman Mariah Haddenham)