Staff Sgt. Michael Gwin, a military working dog handler assigned to the 28th Security Forces Squadron, and Batu, a military working dog assigned to the 28th SFS, perform aggression procedures as part of joint-training with the Rapid City Police Department at the Rushmore Mall in Rapid City, S.D., Sept. 24, 2017. Security Forces members used this opportunity to build relationships with their civilian counterparts and familiarize their K-9s with areas around the city. (U.S. Air Force photo by Airman 1st Class Donald C. Knechtel)