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.

Villagers walk over a tree felled by rain in the village of Punta Caimanes, a place affected by heavy rains in the Izabal region, near Guatemala City, August 8, 2015. Heavy rains have affected eight communities in the municipality of El Estor and five in Livingston, both located in the region of Izabal, with five deaths due to floods, according to local media. (Photo by Josue Decavele/Reuters)

An Iraqi Shi'ite boy poses for a photograph as Iraq Shi'ite Muslims commemorate Ashura in Baghdad, October 24, 2015. Ashura, which falls on the 10th day of the Islamic month of Muharram, commemorates the death of Imam Hussein, grandson of Prophet Mohammad, who was killed in the seventh century battle of Kerbala. (Photo by Ahmed Saad/Reuters)

A handout image provided by the New Zealand Defence Force shows aid supplies being unloaded by Fijian soldiers from an Royal New Zealand Airforce C-130 Hercules plane in Suva, Fiji, 23 February 2016. Tool kits, generators, ration packs, water containers and chainsaws make up part of the New Zealand relief following Tropical Cyclone Winston. The death toll from the cyclone that hit Fiji over the weekend climbed to 29, local media reported ON 23 February. Cyclone Winston, the most powerful storm in Fiji's history, battered the country's main island of Viti Levu and other smaller surrounding islands on Saturday, the Fiji Broadcasting Corporation reported. (Photo by Sam Shepherd/EPA/NZ Defence Force)

A British woman plays a piano designed especially for people who are confined to bed. Date: 1935. (Photo by Mary Evans Picture Library/Caters News)

A woman walks against blowing snow in Evanston, Illinois, on February 8, 2014. (Photo by Nam Y. Huh/Associated Press)

A man rows a boat on the Dal Lake as a woman holds an umbrella during snowfall in Srinagar February 19, 2015. (Photo by Danish Ismail/Reuters)

A woman dancing on the Sphinx. A pyramid can be seen in the background. (Photo by Fox Photos/Getty Images). 1928