Staff Sgt. Monica Bizallion, 11th Security Forces Support Squadron military working dog handler, trains her military working dog, Nirvana, to complete the tunnel of the MWD obstacle course at Joint Base Andrews, Md., Mar. 12, 2015. Completing the obstacles course is part of the training MWDs are put through to better utilize them in the field. (U.S. Air Force photo/Airman 1st Class Joshua R. M. Dewberry)