Senior Airman Victor Diaz, 28th Security Forces Squadron military working dog (MWD) handler, enters the assessment zone with Lezer, 28th SFS MWD, at Ellsworth Air Force Base, S.D., March 7, 2022. Certifications are held when a handler change occurs to ensure that MWDs are competent and able to detect trained odors. (U.S. Air Force photo by Senior Airman Michael Ward)