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)

Spanish director Pedro Almodovar and actress Penelope Cruz chat before the start of the Spanish Film Academy's Goya Awards ceremony in Madrid, Spain, February 4, 2017. (Photo by Paul Hanna/Reuters)

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.

“The Antonov An-124 Ruslan (NATO reporting name: Condor) is a strategic airlift jet aircraft. It was designed by the Soviet Union's Antonov design bureau. It is the world's largest ever serially-manufactured cargo airplane and world's second largest operating cargo aircraft. During development it was known as Izdeliye 400 in house, and An-40 in the West. First flown in 1982, civil certification was issued on 30 December 1992”. – Wikipedia

Photo: The new metro called “Bombardier MOVIA” with 22,50 meters long and 3,2 meters wide is load on a Antonow An-124 plane for transport to India on February 25, 2009 in Parchim, Germany. (Photo Handout Bombardier Transportation via Getty Images)

A sun bear is offered chocolate by a visitor in its enclosure at a zoo in Bandung on January 18, 2017. Animal rights activists on January 18 demanded the closure of an Indonesian zoo after skeletal sun bears were pictured begging for food from visitors and eating their own dung. (Photo by Timur Matahari/AFP Photo)

ABC's “Jimmy Kimmel Live” features a week of guest hosts filling in for Jimmy, starting Monday, October 30, 2017. The guest host for Thursday, November 2 was Jennifer Lawrence with guest Kim Kardashian West (KKW Beauty) and musical guest Linkin Bridge. (Randy Holmes/ABC via Getty Images)

A racehorse is hoisted up before its operation at Veliefendi equine hospital in Istanbul March 3, 2015. A state-of-the-art hospital for hundreds of horses run by the Jockey Club of Turkey at Istanbul's Veliefendi racecourse is the country's oldest and biggest. Grooms and trainers at the equine clinic work with vets and nurses while owners hope their prize runners, often worth hundreds of thousands of dollars, will recover quickly and then run faster still. (Photo by Murad Sezer/Reuters)

U.S. Army soldiers carry an injured soldier who was shot in the leg, through a poppy field on April 24, 2011 in the Arghandab River Valley, Kandahar Province, Afghanistan. The injured was evacuated to a waiting Blackhawk UH-60A helicopter by Task Force Thunder Brigade, Charlie company 1st of the 52nd Aviation regiment from Fairbanks, Alaska. It is feared that as weather improves with the approaching summer that the casualty toll will rise. (Photo by Paula Bronstein/Getty Images)