Staff Sgt. Jonathan Bourgeois, 633d Security Forces squadron military working dog trainer, runs the obstacle course with Drak, military working dog, at Langley Air Force Base, Va., April 6, 2011. Langley AFB dog handlers conduct validation training with their military working dogs in order to evaluate the dog’s ability to patrol and detect threats. (U.S. Air Force photo by Airman 1st Kayla Newman/Released)