Staff Sgt. Michael Gwin, 28th Security Forces Squadron military working dog handler, guides Rex, a MWD, through an obstacle course at the 28th SFS K-9 facility on Ellsworth Air Force Base, S.D., Aug. 22, 2012. When MWDs are ready to retire, they are offered to civilian workforces, guide dog programs, and the dog’s handler before being made available to the public for adoption. (U.S. Air Force photo by Airman 1st Class Kate Thornton-Maurer)