Throughout the course of the long war in Afghanistan, Coalition troops have relied on thousands of military working dogs to help keep them safe, and make their jobs easier. The dogs are trained to detect explosives, to find illegal drugs, to search for missing comrades, or target enemy combatants. Not only are they active on the front lines, but behind the lines they serve as therapy dogs, service dogs, and loyal companions. They also share the same risks as the ground troops, suffering injuries and sometimes death on the battlefields. Gathered here are images of these dogs and their handlers in Afghanistan and back home, from over the past several years, part of the ongoing series here on Afghanistan.

British model Jean Shrimpton at London Airport (now Heathrow), 5th June 1967. (Photo by Dove/Express/Getty Images)

Pakistani street performers sit around fire waiting for customers on a chilly evening in Rawalpindi, Pakistan, Wednesday, November 11, 2015. Some parts of Pakistan are facing a harsh winter. (Photo by B. K. Bangash/AP Photo)

Miss Wisconsin Haley Laundrie competes in the evening gown competition during the preliminary round of the 2015 Miss USA Pageant in Baton Rouge, La., Wednesday, July 8, 2015. (Photo by Gerald Herbert/AP Photo)

A girl shoots a gun armed with blanks at an weapon exhibition during a military show in St.Petersburg, Russia, Saturday, October 14, 2017. (Photo by Dmitri Lovetsky/AP Photo)

Actress Liv Tyler, 40, stripped in shots for the Triumph Essence's Autumn/Winter 2017 campaign in November, 2017. The Essence line is Triumph’s premium offering, with this season taking on the theme of “opulent Art Nouveau”, featuring designs in velvet embellished mesh, Leavers lace and silk satin. (Photo by Rankin/The Mega Agency)

A priest is seen looking out of Abuna Yemata church’s only window. Priests cheerfully tell visitors that pregnant women, babies and old people attend Sunday services and no one has fallen off. (Photo by Ethiopia – The Living Churches of an Ancient Kingdom/The American University in Cairo Press/The Guardian)

1st Place in Wildlife: A male orangutan peers from behind a tree while crossing a river in Borneo, Indonesia. (Photo by Jayaprakash Joghee Bojan/National Geographic Nature Photographer of the Year contest 2017)